Which Rim Size will Fit My MTB? I just got an old MTB, I need to replace all the parts except the frame since the parts are in broken condition, except the sprocket and cassette
I'm a total newbie and LBS here cost crazily high, so I'm trying to replace all the parts by myself
The o.g parts are :

Shimano tourney SIS 3x6 - rusty and broken
Tire size is 26x2.125"
Crankset is rusty and broken too
Brake is also rusty and broken

So the question is

If I replace the group set to - let's say - Micro shift 3 x 9, will the group set work well? Do I need to change the cassette or I can stick with the original one which only have 6 speed and I can't/mustn't shift to 7th gear?

Which rim size will suit the tire? Is it also the 26 inch rim?
If I want to use narrower tire, 26 x 1.5", do I need to find a special rim size which will accommodate the tire width or any 26 inch rim will just do fine?

Thanks

Just replacing the groupset is not enough. 9 speed cassette has different spacing from 6 speed, so the derailleur steps won't match the cogs. For 9 speed cassette, you'll need a new hub, and the new hub is wider than 6 speed so you need to spread the frame too.

There are many different 26" sizes, none of which actually measures 26". For 26 x decimal inches, the correct one is 559mm

See above and What is the maximum or minimum tire width I can fit on my bicycle


Where are stolen bikes sold? I live in a city on the east coast. I recently had my bike stolen. The frame was locked to a bike rack using a u-lock. They either picked or cut the u-lock.

My simple question is: where do thieves sell stolen bicycles?

More specific questions:

If they sell them on Craigslist, how far away are they likely to sell them? Surely not the same city, right?
Are they likely to wait a few months before selling them, in order to let the heat die down?
I imagine flea markets and bike swaps are dangerous places to sell bikes?
What are the top sites on the internet?

Any input is helpful!

I think that there are two kinds of bicycle thieves:

Opportunistic
Professional

An opportunistic bike thief is most likely and opportunistic petty criminal, getting their hands on whatever they can. This kind of thief is just looking for pennies on the value of the stolen items, and will likely try to sell them at a pawn shop or flea market. I suggest checking local pawn shops and the like with your bike receipt and serial number in hand. Do this ASAP

If your bike was expensive and your lock was cut, you may be dealing with a more professional thief. These folks will go through greater pains not to get caught by parting out the bike, or selling it in a different location. In this case, keep your eye on Craigslist in both your area and areas around you, on websites like letgo, or on local Facebook buy/sell groups.

Good luck!


Freehub silent after service I have just picked up my bike from a full service - all parts were taken apart, cleaned, lubed etc. My ride home was really nice and quiet, and then I realised: my freehub is now completely silent.
I have read elsewhere that this could be a bad sign, and that the grease has gotten into the pawls? Should I be worried?
Any advice would be very much appreciated!
Thanks,
Ben.

This is common and not really controllable by the mechanic after freehub service. As long as it's engaging without issue it's fine. The click will work its way back eventually. Thicker lubricants cause more of this but it depends on the design of the hub as well. If too much lubricant or something too viscous was used, that's its own problem, but quieting the pawls down isn't necessarily an indication of that.


How to configure an Avid Speed Dial brake I got this brake lever on my new bike and I am looking help how to configure this. I do not know what purpose the red screw has on the top I reckon this has something to do with the name "Speed Dial" but I cannot figure it out, neither on Google nor on YouTube. I just get shopping links but nothing like an instruction.

Since this is the first time I am using a disc brake I would like to know if the back small wheel (where the brake cable comes in) has the same purpose as it has using V-Brakes?

Avid does provide a user manual for the Speed Dial 7 that describes what the different adjusters do. Just google 'avid speed dial 7 manual':

https://sram-cdn-pull-zone-gsdesign.netdna-ssl.com/cdn/farfuture/Bv5FmtpDsTVHw9CpVeB-YkdnOyinFNaPxEkOXTgCQdA/mtime:1372788167/sites/default/files/techdocs/speed-dial-7-install.pdf

Sometimes you just have to go old school and read the manual, rather than looking for someone to explain it on YouTube  :-)

From the diagram in the user guide one can see that the adjustment moves the attachment point of the cable to change how much cable is pulled for per unit of lever pull.

At one extreme the caliper will engage quickly, but more force on the lever will be required, and less modulation control will be available (will be harder to stop the wheel locking); at the other end the brake will engage more slowly, but you will need less force on the lever and modulation will be easier.


Repairing Presta valves This is the third time that I've had a leaking Presta valve on the tube. There must be a way of repairing the Presta valve rather than having to discard a good tube. Someone did it by applying glue, but I didn't watch closely enough to see where he put the glue. What can I do?

You could try rubber cement however, you will probably still have a slow leak.

You best solution is to prevent the valve from separating from the tube. To do this, I don't put the retaining nut on until after I have fully inflated the tire. Once the tire is inflated, I screw the nut on just tight enough that it won't fall off. You could add some loc-tite but I don't and haven't had a problem. If you over tighten the nut, you are going to cause the valve to separate from the tube.


Can you help identify this classy, German-built city bike? I rode this bike in Germany in the summer and it was great.

I'd like to buy it but I didn't write down the brand, model, or anything.

I just remember that it said on the frame, quite proudly, that it was made in Germany.

It had a 3-gear hub and built-in dynamo lights.

This is the 2015 version of the Winora Aruba, 8-speed bike.
Solid build, but sadly, it's a bit too expensive for my needs as a city bike: costs around €700 new.


Why do shock pumps use a Schrader valve? After reading this question and answer, I was surprised to learn that most shock pumps use a Schrader valve. My mountain biking days are a distant memory, so I'm not well acquainted with the type of shocks that require a pump. But given that high end bikes (the type of bikes that probably feature this kind of shock) almost certainly come equipped with Presta tubes, why would the shocks require a Schrader?

Schrader valves are stronger, for one. Breaking a weaker, smaller valve that has a (perhaps just in my experience) frustrating attachment mechanism for pumps on a $1,000+ fork would be unacceptable.

Road Bicycles

Schrader valves have at least one valid disadvantage on a road bicycle: their larger diameter is a deterrent for use because it reduces the strength of the rim significantly on a narrow-rimmed bicycle wheel (the main point), they use a spring that can wear out to hold their own pressure where Presta valves hold their own (ancillary point, if one at all) and are slightly heavier (retroactive justification from the Presta preachers). None of these matter for a shock.

High-end road bikes were designed for one thing: going fast. Their rim material takes an enormous amount of additional stress from the smaller width, higher inflation rates of the tires, and simultaneously have as much weight, material, and spokes taken away as possible to leave a somewhat durable wheel. In this setup, the hole diameter DOES make a sizable chunk out of the material and strength of the rim, and the smaller diameter allows for more performance and smaller width, lighter weight rims, and so is 'the thing' in the higher end models. Only a 6mm diameter hole is drilled vs an 8mm hole for a schrader.

Non-road Bicycles

Don't confuse 'costs more' with 'better'. In the mountain bicycle / BMX / downhill / trials / non-road bike world, the high end bikes are not all presta. Most utility bicycles (even expensive ones) are schrader for the convenience. They're more of an irrelevant (performance-wise) selection of what the rider wants on these types of bicycles. This isn't because they're skimping in other areas, but the Schrader vs Presta debate doesn't really matter when the rim is wide enough to compensate for the larger hole that must be drilled.

Other Applications

Also note that Schrader valves are much, much, much more common. They're used in refrigerant systems (both on your fridge in your home and in your vehicle's A/C system), plumbing test ports, pneumatic systems, hydraulic systems, and in many other industrial applications as well. I have never seen a presta valve that is not on a bicycle (so if industry is using them, they're cleverly hiding them everywhere I look). This makes the cost of design, tooling, and testing  a much less costly proposition for the manufacturer (and, in the end, the consumer) - by not having to break the trail for using a less common valve in an application it's not been used before.

A fringe benefit of Schraders that may or may not apply in this context is the removable core. When I was a Diesel mechanic the trucks would get ice and dirt lodged in the valve stems, and a simple tool would extract the core, leaving a decent size diameter to expel air, or shove a small screwdriver into to clear debris. Further, if the spring was ever worn, or the seal mechanism not sealing, this core could be replaced without replacing the entire valve stem, and it made depressurizing tires much more tolerable (take the cores out, walk away for five minutes). I couldn't imagine how irritating Presta valves would be. If the seal seat of a presta valve 'wore out', got chipped or otherwise failed on a shock, the whole valve would have to be replaced - which depending on the design, might be a permanent fixture in the shock tubing.


Shimano FC-RS500 11 speed chainset with 10 speed cassette and chain Is it possible to use a Shimano 11 speed crankset FC-RS500 with a 10 speed ultegra cassette and chain. I will be using 105 5700 front deraileur and a 105 5701 rear. Thanks

If you are using shifters that match the derailleurs (i.e 105 5700 series), then yes this will work.

11 speed cranks have a slightly closer chainring spacing than 10 speed to accommodate the narrower chain. Consensus on this site is that you can go one speed difference on the crank and get working front shifting.

I like to point out that the non-series RS500 cranks are somewhat heavier than 105 5700 and I would not call them a great match, but if you are looking for a way to get an affordable compact 110mm BCD crank to work with the rest of the drivetrain it will provide a workable solution.


How to remove a Shimano Quick-Link? I'm currently repurposing an old frame and replacing the drivetrain. If possible I'd keep the old 7 speed drive train the bike had together in case I ever find a use for it. The chain is an HG40 quick-link. There's plenty of info online about joining chains with quick-links but little about breaking and reusing them.

Is there a trick to the quick link to separate the chain so it can be easily reused or do I just need to break it with a chain tool?

The install Tech Doc can be found here.

This is a different link than the Sram type of links. Here is a link to the directions I found that includes the HG-40 Quick link. Hope this helps!

http://techdocs.shimano.com/media/techdocs/content/cycle/SI/Chain/SI_0034B_001/SI-0034B-001_13_v1_m56577569830625422.pdf


Disabling back-pedal brake I have a bike with the so-called back-pedal brake, but since it's for someone who's learning I think that it's more an obstacle than an advantage.

Since the bike also has hand-actioned brakes, can I remove the back-pedal braking effect without replacing the wheel?

What you most likely have is an old-fashioned coaster brake, along with a hand brake.  In reality the coaster brake is probably more "natural" for someone learning -- the hand brake is mostly an affectation designed to make the bike appeal more to boys (of all ages).

But it is possible to disassemble the rear hub and disable the brake in most cases.  There are 3-4 different mechanisms used, so it's impossible to give you detailed instructions, but it would be apparent to anyone with sufficient mechanical aptitude.  (But note that the rear hub, in addition to being very greasy inside, contains lots of little parts, and reassembly requires some skill.)


Split crown "race" possibly dangerous? On some headsets which use a cartridge bearing in the lower assembly, the crown "race" is split. Also, I know a lot of people split their crown race for the ease of installation.

Perhaps I'm overly concerned, but I'm wondering about two things.

Has anyone ever cracked a crown race during use? If this is something that can happen, a split crown race might shatter into pieces..
The crown race is held somewhat snug by the chamfered edge of the bearing, which suggests it might prevent a broken crown race from falling of the fork. Has anyone ever crashed due to the crown race / lower headset assembly failing?

Edit: I ask this because I consider splitting a race. I'm switching out a RS Reba for a Surly 1x1 fork, both of which have a crown seat diameter of approx. 30mm (as do all 1.125" forks, as far as I know). I tried setting it using my "specialized race setting tool" (i.e. some PVC piping and a mallet) and plenty of lube. No luck however, the pipe started to shatter but the race wouldn't set :-(. It seems like the seating is just a hair too wide for the race to seat. As far as I see there are two options: file down the crown seating a bit, or split the race. The latter seems easier; also I'd rather modify a 3€ part than a 50€ one. But only if I won't loose my teeth over it :-P.

I've never cracked a crown race after assembling many different bikes with different fork/headset configurations. Split crown race makes things far easier and it means one less specialty tool that you need to own or access to get the job done. I've never had an issue with split races either.

As for splitting your own, lots of people do it without issues, if you go this route, I would make sure you gently file the edges to make sure it is deburred with no sharp edges. For how infrequently you need to install/fiddle with a crown race, splitting would however be a last resort for me since you can usually set them with a piece of appropriately sized PVC pipe and a mallet.


How can I reach upto Olympic level competitions? I am 20 years old. My height is 1.7 meters (5 foot 7 inches).  I live in India.  I have cycled since I was a kid just for enjoyment.  I have no idea how I will reach  to world level competition like Olympics. It is my dream. or is it too late?
Is there something which will tell me early on whether i am capable of doing it or not, like a first test whether I am gifted with cycling skills?

There's no way we can answer this question for you. The people who reach elite-level competition in cycling have extraordinary natural gifts, dedicate enormous time and effort to training (20+ hours per week), and are incredibly motivated (to train intensively for 20+ hours per week, etc).
If there's a local cycling club you can ride with, do that. If there are any races in your area, enter some races. See how you like racing, and see how you do. Start reading up on training methods and learn what you can. Usually the people who have those exceptional gifts rise to the top pretty quickly, but even if you don't, don't let that discourage you from having fun with racing at a local level.


Are Hollowtech II bottom bracket normal? I've just installed a brand new Ultegra 6600 crank/bb on my brand new frame. Everything is fine and properly installed, but the crank doesn't rotate as freely as a square taper BB. The bike is not yet ready to be ridden waiting for some parts.

Will the bb break down?

Assuming you have the BB installed properly (no cross threading) it is normal to have a little bit of resistance when they are new.  But honestly they don't feel as "free" as a square taper BB because of the resistance from the bearing seals.

Also, be sure to check the drive side cup of the BB every 3-6 months.  If you ride in wet conditions aim more for the 3 month side.  That cup has a tendency to seize up.  It happens with all steel ball outboard/hollowtech BB's and the only answer is a ceramic bearing model or a Chris King BB.


What are the advantages of angling your saddle down? I have seen a few people do this where their saddle was angled down a bit. Why would someone do that?

In general, I don't know why one would do this. Especially men.

Here's what Sheldon Brown has to say, and I tend to agree:
"If the saddle is tilted down in front, the rider will tend to slide forward onto the narrower part of the saddle. Women who are riding on saddles that were designed for men frequently tilt their saddles down. This will relieve some of the discomfort from the saddle itself, but creates new problems: The downward slope of the saddle causes the rider to tend to slide forward, and this can only be counteracted by pressure on the hands. Thus, poorly-angled saddles often are the cause of wrist, shoulder and neck problems, due to carrying too much of the rider's weight on the hands."

Lennard Zinn mentions that a "very slight" tilt in either direction may be optimal for some riders; but no more than ~2 degrees. Basically the same reasons that Sheldon Brown mentions. The downward forward tilt adds pressure on the arms, back, and shoulders due to sliding forward.

You want your "sit bones" to be on the widest part of the saddle. If you slide forward, the pressure will shift from the sit bones to the perineum; and that's probably a bad thing. There are special cases for tilting the saddle nose downward; but for the general rider it's not necessary.


Arguments for/against bike lanes? What are the arguments for and against bike lanes? Can anyone summarize the best reasons they're good for and bad for cyclists and automobile drivers?

For example, Are there some environments particularly suited for bike lanes? Are there some types of locales that would be particularly suited for them, where they wouldn't cause resentment?

AGAINST

One of my primary issues with bike lanes is that motorists tend to think that you have to stay in that lane.  So when you have to move right because of debris, garbage cans or parked cars in the lane it further annoys ill-informed drivers.

Additionally, drivers come to expect you to be out of traffic, riding on the shoulder, and will squeeze by you closer.

Many bike lanes are placed immediately to the left (traffic-side, may be right depending on the country) of the parking area, so if you remain in the bike lane you are in the "door zone".

Bike lanes tend to increase confusion and conflict at intersections, either forcing the cars to cross the lanes in an awkward manner, or enticing cyclists to filter to the front of the lane and possibly blocking turning actions by motorists. Bike lanes encourage passing on the right, which can be a very dangerous action for the cyclist.

Finally - by law in most places every lane is a bike lane... there is no possible way for designated bike lanes and routes to be marked to every destination I would like to visit, and by law when I am in the lane I am traffic, I'm not blocking traffic. (sorry, I get a little militant about bike lanes, especially when they are the primary focus of improved cycling infrastructure rather than wider roads with calmer traffic.)

FOR

As someone with some experience teaching workshops for new bike commuters, I find that the existence of convenient bike lanes and multi-use paths makes taking those first trips easier.  Novice commuters feel more comfortable riding on a marked bike lane, even if they don't realize that they may be marginally less safe in a bike lane at the far right edge of the roadway, generally a riskier position.

There are some places, like one particularly popular area in Salt Lake City, where rather than position a lane demarcated with white lines to the side of the travel lane, the DOT painted a wide green lane with bike icons almost in the middle of the right-most travel lane and erected signs that read "Bicycles Allowed Full Use of Lane."   This is not a bike lane, but a hybrid or shared-lane, and  I love it because it reinforces the fact that bikes are traffic, and roads must be shared.


Electrochemical corrosion - bolts holding axles I suspect similar questions like this have been asked before, but rules on this stackexchange require that I create a separate thread.  So please bear with me.
I believe galvanic corrosion happens between electrically connected dissimilar metals and that it is accelerated under certain environmental conditions.  I have two cases that I want to understand.
The first is a Paramount Series 3 all stock components and in pristine condition, and the second is a 2020 Cinelli Tuto frame with some random assemblage that I do not have prior history of, and it has rust around the crank, the rear toothed gear, and the bolts that attach the front and real axles (hubs?) to the frame.
The Paramount has shown minimal corrosion over its 20 year life, and specifically around these various locations.  It uses Shimano quick-release skewers for the front and rear wheels with Shimano RX100 (HB-A550) wheel axles. The Cinelli uses the HJC DA-17 ETRTO axle attached with steel bolts. Based on its sheen, the axle seems to be made from aluminum (I could be wrong).
Question: generally, is this steel-bolt-aluminum-axle combination common?  Would that be true of the Shimano, and do I just need to get weather treated skewers for the Cinelli, or just the right bolts?  It's possible these bolts were purchased from McMaster without any attention paid to corrosion resistance.
Thanks!
Edit: Adding pictures, as suggested by Armand below.

Edit: I've incorrectly supposed the way the galvanic corrosion  between chrome moly steel and an aluminum alloy happens.  I incorrectly thought both metals would be corroded, however, in galvanic corrosion it is the only one of the metals that is corroded because it acts as the sacrificial anode part of the circuit. In fact, the other metal is imbued with corrosion protection as the cathode in this reaction.   One can compare the anodic index of differing alloys to assess the risk of galvanic corrosion when the differing metals are in contact.  The higher an alloy's anodic index, the greater the chance it will end up being the corroded anode.  However the risk of galvanic reaction is determined by the amount of the difference in two metals anodic indexes. A larger difference in the indexes of two metals, the greater the risk of corrosion of the one bearing the higher index. The risk is also mitigated by the environment the two metals will be subjected.  For the purpose of this question, it would be the aluminum alloy would be metal corroded in such a situation. Aluminum oxide is whitish in color and would look nothing like the red tones of iron oxide corrosion seen in steel corrosion.  Thus, seeing redish oxidation as the OP notes is not caused by galvanic corrosion, but does infer some sort of steel oxidation going on.  Unusual for such a new frame of corrosion resistant chrome moly steel.
Still a good deal of speculation here, but as the Cinelli Tutto's frame is "Columbus Chromor" --from the Cinelli Tutto website--which is chrome moly steel, it may not play well with the "random assemblage" of components someone has selected. Your rust issues may be caused by galvanic corrosion if the crankset is alloy explains rust around the crank.  Often the spider and/or the first few cogs, if not all the cogs, of a higher end cassette will be an aluminum alloy. At the dropout area, even with a low profile of material near the cassette, the frame or the wheel fixing nut could be the source of the rust stains around the cassette. I wouldn't think it to be the chrome moly steel, but???
I speculate too that the axles of the wheels may be an aluminum alloy. The Tutto is sold as a frame set apparently, and it's easy to make the leap that someone uninformed about the risks of galvanic corrosion has selected nice alloy parts and placed them in a steel frame with inadequate protection against such corrosion.  Perhaps even the wheel axles are aluminum alloy and reacting with the steel fixing nut.
I submit that a 2020 frame set could not yet be corroded enough to be damaged enough as to be unrideable if the parts are removed and the bike cleaned thoroughly.  As you've noted, environmental factors could catalyze the corrosion.  One can imagine one wet ride with the road spray and it's countless molecules of contamination left to dry in place, the grease separating the differing metals being washed away.  Good opportunity for galvanic corrosion to begin.
Disassembly is certainly in order and after cleaning reassemble with parts--whether same or a different assemblage--but with the appropriate amount of waterproof grease to form an effective barrier between the dissimilar metals.


Can I upgrade to Synchro shifting on a 10s Di2 bike? (Ultegra 6770) I bought a second hand bike with an existing Ultegra DI2 6770 groupset, which is a 10-speed group.  I would like to upgrade the components required in order to have syncro shift on it.

As far as I know syncro shift is not available for 6770 (10-speed Shimano Ultegra Di2). For 6870 (the first 11-speed Ultegra Di2 version), Synchro shift is available if we update the battery to the BT-DN110. (Note: the battery houses the computer system that enables Synchro shift.)

Thus I am wondering what components I need to upgrade from a 6770 groupset?

I just installed a Di2 6770 10spd front and rear derailleur with a BT-DN110 internal battery.

I can confirm that once I update firmware on all the components, eTube does NOT allow me to set up synchro shifting.

Very disappointed considering the battery has all the hardware necessary to support it.


Keeping a 2006 Giant SCR 3 on the road - 9 speed to 11 speed? I have a Giant SCR 3 which was a freebie from a mate, who had it new.  It's approx a 2006 I think, and I've had it about 5 years.  I've spend a relatively small amount along the way at the LBS, keeping it going.

Due the serious mileage it's seen between the two of us, the following are now clear;

The original Tiagra 9x3 groupset is nearing End Of Life (confirmed by friendly LBS, who don't try to sell me anything I don't need)
The original Alex rims are WAY beyond the wear indicators, although, nothing bad has happened yet!
Braking is now a serious effort on the hands (needs new cables I guess)

As much out of nostalgia for my first decent road bike, I'm tempted to give it a new lease of life.  I have other bikes, but this is/was my go-to commuter, and old enough to lock up in town on a night out too.

I believe the 9 speed is now obsolete in Tiagra?  So do I go Sora 9 speed (Sora in 2019 perhaps similar standard to 2006 Tiagra?)
OR, as I need to change wheels too, is this an opportunity to go to new 11 speed Tiagra?

Am I missing a trick here? Can I just by new cassette, chain-rings, chain, and keep it going...

Thanks all

James

PS: Little bike DIY experience to date, although I am mechanically minded.

I think your minimum refurb to bring the bike up to a good standard would be: new wheels; bottom bracket, chain, cassette and chain-rings; housings and cables (shift and brake); tires, brake pads, bar-tape; and a total, thorough cleaning and re-adjustment. This is assuming the derailleurs and shifters are actually working OK, and your LBS just means 'obsolete' when they say they are at 'end of life'.

That's a fairly big chunk of the bike, so you may want to go the whole way and upgrade the groupset. Personally I'd want at least 10 speed as an upgrade - Current Tiagra 4700 is 10 speed. Another option is looking for lightly used 105 5800 or Ultegra 6800 (or perhaps even R7000 or R8000) 11 speed components.

I'd look for a good set of lightly used wheels. As tech has moved to disc brakes and thru-axles you can probably find some really good light and strong rim/QR wheels for reasonable money.


Is white spirit a too aggressive degreaser? Talking with a friend about maintenance on bikes, he told me he uses white spirit to degrease the chain, as it is effective and also offer some kind of waterproofing in case one forgets to lubricate the chain again.

Talking with my bike dealer he advised to not use it, as it is too aggressive and would also remove the lubrification from within the chain bearings. He suggested using a dedicated soap.

Who is right?

How do you forget to lubricate a chain after cleaning?  If this is a possibility, you a would be better not to clean the chain at all.

White spirit is a generic name for different products, exactly what it means depends where in the world you live.  Some have a flash point of 20–30°C — extreme care is needed using it. Others with higher flash points and lower volatility are safer (but not entirely safe). All are hydrocarbon based and environmentally unfriendly if disposed of improperly. Care should be taken using them

To understand the arguments of what cleaner is best, you need to understand chains.

New chains come factory lubed with a very robust and long lasting lube that is much better than anything you can apply. The last thing you want to do is use a cleaner that will strip this lube off the chain, in fact, for the first few hundred kilometers no cleaning is probably best.  White spirit is one of those cleaners. Once the chain is older, and this lube is worn off, it needs replacing. Stripping the replacement lube off completely is not problem — it's easy to lube the chain and get the same level of lubrication as you had.

So should you use it on new chains? No way. On old chains, it won't matter. Question is when does new become old? Who knows. Easy answer and most (profitable for bike shop) is use a dedicated bike chain cleaner (you buy from them).

In the end I don't think it matters, as long as you are cleaning the chain regularly and lubing it properly.

There are plenty of questions on this site and discussions on the internet about the various religions of chain maintenance you can delve into if you desire.


Leaking lever - Shimano brakes M365 i recently took my bike to the LBS for brake service. Everything was fine until i noticed that the right lever (back brake) was leaking.

Every time i press the lever, it sort of "burps" a bit of oil and makes... funny sounds. (seen in picture 2)

I tried un-tightening the top cap, which really helped a lot but im not sure about the origin of the problem.
I should note that when i took it to the LBS for bleeding, the pads were 80% worn. After i replaced them, the problem appeared (the mechanic said it's fine if you do that, but i doubt it). I should also note that i torture them a lot.

The first thing to check is that the rubber gasket in the brake lever reservoir is fully intact and in place. They can get both torn and clamped out of position, and that would be consistent with having just been opened up for bleeding. Make sure the reservoir is turned horizontal when open so fluid can't spill out.

If it's leaking anywhere else, there's not much that can be done other than replace the lever.


Road bike getting punctured often on poor roads I brought my road bike to Mumbai where the roads are pretty bad (lots of potholes, gravel...), I've been getting a puncture roughly every 2 weeks. The tires are about 6 months old. They are a bit worn out, but people I ask here say it's fine.

What are my options to deal with this? Should I line the tire with old tubes?

Kevlar tyres.  Or at least kevlar liners.  Check the pressure regularly, especially if running on patched tubes.

I suspect sharp debris/litter may be the problem

Lining with old tubes doesn't seem like a good idea - they're no stronger than the tube you've got, and add significant bulk affecting how the tube sits.

For properly bad roads, I wouldn't ride on road tyres - get something designed for rougher urban use.  All the major tyre manufacturers make something with kevlar, slightly thicker rubber and a bit of grip compared to road tyres.  I've fitted continental's version to a mountain bike for city use, and it will take much more sharp stuff than MTB tyres.


Which downtube friction shifters work with 2021 Campagnolo 11-speed cassettes, and how well? Another question from a few years ago asks about Shimano 11-speed derailleurs; I have a related question about current (2021) Campagnolo equipment - I'd like to understand what downtube (friction) shifters will work with a Campagnolo 11-speed derailleur.
What is the cable pull required between top and bottom gears, and is it the same as for 8/9/10-speed systems? I thought that the total derailleur travel was the same, just with narrower spacing between gears, but I see that Dia-Compe make a dedicated 11-speed shifter with a larger diameter for greater cable-pull.
How well do friction shifters work with Campagnolo 11-speed cassettes (if at all)? And which ones?

Friction shifters are infinitely adjustable - by definition they don't have stops or detents for each gear position.  If they did, they'd be called "indexed"
So there are only three attributes your friction shifters need to run effectively

Total range - the lever must be able to pull enough cable to actuate the mechanism across the whole cassette.
Accuracy of your fingers/ears - The rider has to be able to place the chain in-gear without rub, while riding.  On a 5 speed block there's a lot more space between cogs, and the clatter is obvious.  For a 12 speed block, the cogs are closer together so the sweet-spot is smaller.  Can you find it by feel while riding?
Resistance - the friction lever needs to be able to hold its position and not drift, which would give you a spontaneous up-shift.

An addendum - the frame/bars needs some way to hold your friction shifters.  Historically that was a set of brazed-on mounts, but a modern frame won't have them so you'll need to use a band-on set of mounts that can fit around your down tube.
Stem shifters are another option, and bar-end shifters are also available in indexed or friction mode.


Sprayed Lubricant on Hydraulic Brakes, how to clean? I was spraying some lubricant on my chain and accidentally sprayed on my hydraulic brakes and it affects my bikes braking power massively.
How do I clean this off?

Rotors can always be cleaned; sometimes you have to use scotch brite or sandpaper, but usually brake cleaner alone will clean them fine. Make sure you clean the areas around the rotor, especially the hub, to make sure the contamination doesn't drip, "sling" or migrate back onto the rotor. The best brake cleaner is perchloroethylene (original red-can Brakleen) because it is non-flammable and relatively gentle on rubber, paint, aluminum etc.; however all commercial brake cleaners clean the brake rotors themselves just as well. If you don't have brake cleaner you can try alcohol or degreasers.
The brake pads may be ruined. You can try drenching them in solvent or sanding them down slightly, but it might be better to just get new ones. If you use contaminated pads, you will have to repeat cleaning the rotor, so trying to rehabilitate brake pads is often not worth it.


Any help with the History of Guaranty Quality Supreme Fleetwood Bicycle 1963 – 64 Original Goodyear Wing Foot “175” tires hold air with very good tread and no dry-rot.  Wheels marked M.O. MFG. Co. (Murray Ohio Manufacturing Company).  Bendix RB2 Red Band Automatic 2 speed Hub. Union Diamond Tread Pedals made in Germany.  Handlebar Stem marked A.S. - 66.  Fenders and Chain are thick, sturdy.  Very nice Mesinger Seat made in USA

According to the Everything Murray Bicycle your serial number:
M9501JX26172612 (Not sure about the "J". Best I could tell from the picture)
indicates that
M9 = 1969
The "X" begins a string that indicates who the bike was made for.
For example "X13" would be a Murray branded bike.
If you ordered enough bikes from Murray they would put your brand on the bike.
"X7" = BF Goodrich
"X10" = Westernflyer (Western Auto)
"X12" = All Pro (Kmart)
Your bike is "X26" so according to the chart it was made for "Guaranty (Guaranty Bicycle Company - St. Louis Mo.)
The Guaranty Bicycle Company or Guaranty Cycle Co. was a shop located in St Louis Mo.
Here is a scan of their 1952 catalog. The badge on the cover is an older version of the head badge in the picture
At one time they were able to buy enough bikes from Murray to have their own brand.
According to the USPTO the Guaranty trademark was owned by Donald O Rehm and it expired in 1996.
There is no bike shop named Guaranty Cycle Co. in St Louis today. I can find no information on the history of the shop.
Hopefully this information will enable others to find more details.


Healthy riding for asthmatic I have asthma and find it very hard to ride for a very long time without tightness in my chest. Is this safe for me? I have knee pain as well and I find bike riding helps with the knee pain, but asthma is a different story.

I can not give any advice, but I can present my personal story and experience. When I was a child, I was diagnosed with asthma. I needed to take a lot of medications in order to fight against asthma. I stayed also a lot of nights in hospital. At the age of 11, doctors suggested my to try endurance sports. I have chosen cycling. In fact, I really had a lot of problems with breathing in my first two years of cycling career. I needed to take Ventolin (Salbutamol) every training. During the years, situation became much better. After some years of training, I became competitive enough on a national level. In line with this, I have never faced any major problems with asthma again. I am racing now Ironman triathlons without any medications. I only sometimes have problems with breathing when there is a mix of hot and cold weather. Usually, when Autumn is transitioning in Winter I need to take one or two inhalations of Ventolin. Anyway, I also avoid riding in fog.


What clothing is best for wet weather/cycling in the rain? I tried wearing a raincoat to keep out the rain, but find I get hot and sweaty inside. So my question is, what clothing do you find works best for you when cycling in wet weather?

Thanks.

Lightweight polyester or microfiber materials do the job. Pearl Izumi is my favourite. Bike specific rain jackets are a must if you are looking for comfort. Generally they are very thin and have air vents in them. There is no reason to wear heavy rain jackets. Instead, layer up up with a base layer (often merino wool or synthetic thermals) + mid layer + the shell (which is the jacket). That is probably the most common layup for cyclists and it will keep you warm.


Can’t seem to put the wheels back on the frame I’ve removed both wheels to do some deep cleaning. And even though, I’ve removed the wheels before I would immediately pop them back on without a problem. This time I left them out for a few weeks, and now can’t seem to put them back on. It’s a quick release , but the skewers only screw until a certain point, where the ribbed bit ends which is far less than the necessary to tighten the wheel to the frame.

I don’t think I’m missing any parts, so what basic step am I missing here? Any help would be greatly appreciated.

That's not the correct skewer for the wheel. I think you likely are using the rear skewer in the font wheel. Front hubs are typically 100mm between the drop-outs, rear are 130 or 135mm (or even 145mm on some mountain bikes that have stronger through-axle designs).


Should I replace my 10000km Schwalbe Marathon Plus Tour with a 2000km Schwalbe Marathon Winter Plus? Background
I have one Schwalbe Marathin Winter Plus tire that is in good condition (used for 2000km, 10 months old). Below the winter tire with spikes removed.

On the bicycle at present is a Schwalbe Marathon Plus Tour (used for 10000km, 3 years old). Below the summer tire.

I am moving to a country where I will not need spiked tires. Because of weight limit I cannot take both tires with me.
I was thinking of replacing one summer tire with one winter tire. I normally only cycle on tar.
Arguments for replacing the summer tire

10000km old / 3 years old
1cm long gash on side of tire due to piece of glass. Gash narrows to a small hole where the tube is visible. I put a boot on the inside.
Winter tire only 2000km old / 10 months old and no gash

Arguments for not replacing the summer tire

Summer tire still "looks good". Tread still looks deep. Tire not smooth. The blue of the inner layer is not showing.
From experience with Schwalbe Marathon tires, gash is not a problem (this is the 3rd large gash on 3rd pair of Schwalbe tires)
Concern: the holes for the spikes on the winter tire are prone to punctures ?
Concern: the rubber of the winter tire is different than the summer tire rubber. The winter tire will wear off faster ?
Concern: winter tire has more nobbles, i.e. the summer tire seems thicker

(Detail: Of course I also have a front winter tire. But the front winter tire has a large 2cm gash also caused by a piece of glas.)

I don't think the holes in the winter tyres will be prone to punctures without the spikes in them. They're a very small target. I have had damage from the inner end of the spikes themselves wearing through the belt on tarmac (occasionally icy).
These winter tyres aren't as tough as the marathon plus (tour) though, both in terms of overall puncture protection and wear - winter compounds are softer. They still probably have more life than marathon plus with 10000km on; at least at the back that's about how much I get.


does anyone know any forks i can fit on my specialized pitch XC bike so I'm looking to get a new for fork for my Specialised pitch, and it's a quick release wheel so need quick release forks, does anyone know any forks?

A bit more info on the year, make, model and size of your bike would be helpful. Assuming you're talking about a suspension fork, you'll want to make sure to get one with matching wheel diameter and axle type and width and brake type, and that the axle-to-crown distance is similar so the front doesn't tilt to far up or down compared with your current fork. As mattnz pointed out, you will also need to make sure that the steerer tube is the same type (straight or tapered) and the same outer diameter as your current one.


Is there a cornering warm up routine? I noticed my cornering confidence improves as my ride progresses (which seems be a little odd).  Is there some sort of cornering warm up routine I can perform before a ride to help be confident throughout?

There's a common enough drill that we teach kids on our HS MTB team that could also serve as a warmup.  The idea is to practice keeping the body vertical (and off the seat, of course) while turning the bike into the turn.  The foot on the outside of the turn is kept down.  A variation (an "I trust my bike" exercise) is to maintain that posture while keeping the bike moving straight-- essentially riding straight on the side of the tires.  The first exercise is more useful, imho.  We've seen an improvement in confidence as the kids understand a bit of the physics of the turn and see that there's more to it than, "fling yourself into the corners and hope the brakes are good enough".


New, cheap mountain bike: What's most likely to break? I have a very cheap (less than USD $100), new mountain bike I'm about to break in on a 2-4 hour ride on a mountain trail. I'd like to be prepared for equipment failures or problems - can anyone suggest what's most likely to break (or have problems) first?

I already have a spare inner tube (and pump!) to handle a punctures, and expect to have a sore rear end, anything else?

(thanks for the articles warning about cheap bikes - I should probably add that I will use this bike only once a year at most, and can't afford a better one anyway - if not for cheap bikes I'd just be walking. For anyone coming across this question considering buying a very cheap bike, see the link posted in the comments and make sure you know what you're getting into!)

Update:
Thanks for the answers so far. Thought I'd do a quick post-mortem for anyone interested. I went on the ride (Oaks fire trail, very scenic, good fun - Blue Mountains, NSW, Australia).

I managed to escape without notable failures on the bike, though I think the cheap suspension fork had already seized up and the derailleur only changed gears when in the right mood.

In our group of 15, we had 3 flat tyres and a broken chain (all on $1000+ bikes, oddly enough - maybe they were just riding them harder).

The most unexpected problem was with replacing punctured tubes on the expensive bikes. The tube valve hole in the fancy rims wouldn't fit the spare tube's  larger (standard car size) valve, and many pumps couldn't fit the fancy tubes (to re-inflate them once patched).

Information about the specific components would help. I am not sure what will break first, but the derailleurs will probably be the first component to need servicing - especially if you purchased this bike from a sporting goods retailer instead of a bike shop. Brakes will probably be needing some love in the near future. If you ride on trails at all the fork will probably end up needing some maintenance quickly. The wheels will also probably go out of true pretty quickly as well.

One thing you can do to help keep the bike in good running order is to frequently put chain lube on your chain to keep it, your derailleurs, and cassette well lubricated.


How does one revitalize chrome lugging without harming the finish of the paint? I have an older bike that's in the middle of being rebuilt and I need to take care of the chrome.  The paint is still on the bike so I need to be careful of any chemical or physical processes that may discolor or destroy the finish.  How can I best get that mirror finish back on my pitted lugs?

In the UK I've had success with Brasso, a cloth and lots and lots of elbow grease. Don't apply it with anything so harsh as wire wool or a scourer, just the impregnated wadding that comes with the product.

Unfortunately Brasso in the states is a slightly different composition so I can't vouch for it's efficacy.


How do I remove this back wheel axle nut? 90s Peugeot mountain bike It's a 16mm nut that won't turn, and I don't want to bend my cone wrench.

The other side came off easily but was a normal nut. This side seems to have some sort of lock/ hole for a pin but I'm not entirely sure what to search for in regards to it

http://s29.postimg.org/3v75cum3r/image.jpg

I've uploaded a picture, notice the little dip / semi circle hole on the end of the axle? I'm pretty sure this is related to whatever's stopping me from turning the nut

That lock groove is for a washer between the cone and the locknut, and there's no way to have a nut on the axle that locks into it. So you can ignore it.

What you need is a proper 16mm ring spanner. Even an adjustable wrench could well strip that nut. If you have to go to a bike shop or some other workshop to use one, do that. Or just buy one, since you're likely to need it.

Commonly those nuts are done up ridiculously tight for a reason. Often it's because that derailleur protector is only held on by the one nut, so if bumped it will tend to rotate and loosen the wheel nut (the one you're trying to undo). Rather than getting a proper derailleur protector (and that keys onto the frame), a "solution" is just to do that nut up really tight. Which also puts pressure on the cones, so people will often back the cones off a little to stop the wheel binding. It's a classic case of "now you have two problems" (or here).


Can my fork support disc brakes? I want to put disc brakes on my bike but I do not know which type to put on

In order to fit a disc brake, you need a compatible fork and a compatible wheel, plus a compatible brake lever.

Your fork does have a disc brake mounting already designed in, it is an International Standard (I.S.) mount. Most mtb brakes now are Post Mount fittings so are fitted using a simple adapter. You can see the differences here or search around images.

To fit a disc brake you need a disc compatible wheel of the correct diameter (check the current size), the caliper and maybe a lever. If you have V-brakes now, you could add a mtb specific, cable-operated caliper to the existing lever with a new cable and housing. Alternatively you can get pre-bled hydraulic disc brakes, comprising the lever, caliper and disc, ready to use out of the box. N.B. there are two standards of disc mounting, 'six-bolt' and 'centre lock', match this to the new wheel hub.

Bear in mind that because you need a wheel change, changing to a disc brake could be expensive relative to the value of the bike (which is of course not always monetary). It's up to you to decide the best use of the money; that might mean upgrading this bike, or it might mean saving up towards a disc brake specific bike, new or used.

An interim upgrade could be a high quality brake of the same type you have; if it is a V-brake, good models are quite affordable and do make a noticeable difference over basic models. Also, with rim brakes particularly,  high quality brake pads noticeably increase performance for not a lot of money.


Bicycle with 26x1.95 tires Can a bicycle with 26x1.95 tires on magnesium alloy wheels be upgraded? Say 26x2.10?

Most of the time that should work. You have to make sure it isn’t a Schwinn special sizing (Any of the S(1-6) sizing). Make sure the tire ISO and wheel are 559mm.

For this bike, I would say with 99% confidence that would work.

Personally, I would look elsewhere if you were looking to upgrade something. A used bike from a reputable brand on Craigslist will perform a lot better for the same cost.


45 day old SRAM rear derailleurs jumps gears have a 1x12 SRAM NX drivetrain on a fairly new full suspension MTB.
Been feeling great but yesterday it began skipping a gear when I shift. That is, if I start in 1 and click 4 times I wind up in 6th ring rather than the expected 5th.
The top and bottom limits seem ok because when I shift all the way through I do wind up on 12.
I know cables can stretch and I could bring in to a LBS but trying to avoid that.
I’m pretty handy with my bikes but derailleurs remain magic to me. Can anyone point me to a some easy advice or a great YouTube video.

When the shifting skips over a cog on the cassette gears, this is because the derailleur hanger (or less often, the derailleur cage) is misaligned. That is, the small sacrificial tab of aluminium which is between the frame and the derailleur proper. This can happen easily on any bike if it is mishandled or the mech strikes a rock etc., the age of the bike isn't a big factor.
The solution is a derailleur alignment gauge, which a shop will have and can check the alignment for you quickly and easily. You could buy one yourself but they aren't the most common home tool because they're pricey and hopefully you need one only rarely.
Cable stretch would affect each shift equally, the cable loses tension and it is sluggish to change into every gear, because the start point of the indexing is out and the error carries over to all shifts equally.
Your problem is that it skips past just one cog completely, part way up the cassette, which is an indication of misalignment. Playing with the cable tension could bring a little improvement, but if you are not proficient with indexing adjustments, the misalignment will cause you added frustration, even if you follow the instructions correctly. In this case it's well worth checking the hanger alignment at the same time as any indexing adjustments.


Chain touches plate between pulleys I've replaced chain and dropout hanger. The rear derailleur is Shimano Claris. When I'm turning pedals chain (Shimano hg-71) is touching small plate (marked with red arrow) between high (closer to high) and low pulleys with loud metal sound.
The derailleur works in general and I'm able to switch between all 8 gears.
How I can solve this issue or is it broken?
There are also video, where it is obvious in action
https://drive.google.com/file/d/1aEuVgdymEKdN0EWf3sq25GhJhyD7SK0k/view?usp=sharing

UPD: Solved - I've bought new derailleur(claris ~20 eur) and I was able to configure it very easily. The problem in old one is really in broken inner plate geometry. This probably happend during my accident. Plate is bent in X axis towards towards the chain, which makes it really hard to bent back.


Can a chainstay's length vary? My gut is telling me that this is a typo, but here's what I'm seeing.

I'm looking at the 2017 Rocky Mountain Element which seems to feature a chainstay that can range from 439-437mm.

For comparison, the 2017 Rocky Mountain Instinct, seem to feature a fixed chainstay length of 452mm.

For the other parts of the geometry that have a range, I get why for these as the suspension compresses and changes the value. However, I can't see how the chainstay would change in length in this case.

Apparently, there are differences not readily apparent on the frame graphics. Per Rocky Mountain:

  The decision to include variable rear center information on the
  Element relates to the redesigned linkage, hence why the Instinct
  doesn’t show any change. The rearmost pivot is much closer to the rear
  axle on the Instinct, so the change is virtually nonexistent.


First time purchase of cycling shoes? What should one look for when purchasing spin shoes?

I will mainly be using these for indoor spin classes and occasionally on a road bike.

You would probably want a shoe that's designed for an SPD clipless pedal. In my experience most gym spinning bikes use an SPD type pedal. As long as your road bike has SPD pedals, you can use the same shoes.

I suggest going to a bike shop or outdoor store with a good selection of cycling shoes and try on a few pairs so that you get a good fit. Good fit is subjective, so that's why I say to try on a few. Mountain bike shoes are probably the best option. They look like sneakers and have SPD mounts. Also, the SPD cleats are recessed in the tread of mountain bike shoes, which makes walking more comfortable. In addition they work just fine for occasional road bike riding...that is as long as you have SPD pedals on your road bike...

Now that I think about it. It's possible that your gym spinning bikes are equipped with "Look" type pedals. If that's the case, you'll need a road shoe with cleats that match your road bike. I travel a lot and take spinning classes when I travel; and very rarely run into spin class bikes with Look pedals. So, odds are, you want an SPD compatible shoe.

For the typical spin class bike, you can adjust...

The seat height
The seat fore/aft position in relation to the handlebars
The handlebar height

Often, but not always, the spin bike will feature a double-sided pedal. Typically, one side is "strap in" and the other is quite often SPD cleated.

So, when you get to your spin class, make sure that the bike is adjusted correctly. For me, I try to duplicate my road bike as closely as possible. Otherwise, and especially if you're new to it, the spin class leader should make sure that you have made the correct adjustments on the bike.

And how to choose the shoes? Complicated? Not really. With the OP criteria, just get a pair of good-fitting mountain bike (SPD) shoes, and you'll be fine.


Frame sizing: "medium" vs. inches vs. centimeters How in the world does 17-18 inches match up to 53-54 cm??

I was looking up bicycle sizing charts and found the ones on the Evans website interesting, if somewhat confusing. For example, see the chart for Hybrid frame sizes: http://www.evanscycles.com/help/bike-sizing#hybrid

Looking at the suggested frame sizes, I guess I don't understand how the inches vs. centimetres match up. A frame size of 17-18 inches or "M" is listed as being equivalent to a frame size of or 53-54 cm, however, a simple conversion shows that 17-18 inches is roughly equal to 43-46 cm. Strange!

Thanks!

Essentially, bicycle frame sizing is inconsistent and possibly insane. Try the bikes out. Don't rely on a single number for the size.

Theoretically the size given is the length of the seat tube, but there's a lot of inconsistency in how that's measured.

Usually a frame size given in inches is a mountain bike frame and a frame size given in centimeters is a road bike. A mountain bike frame will have a higher bottom bracket in order to clear obstacles better, and may also have a lower seat tube (to lessen the odds of your crotch colliding with it when dealing with rough terrain), so you can't simply convert one number to the other. If you look on that chart and compare the "hybrid" sizes to the "road" and "mountain" sizes you'll see that hybrid cm is close to road cm and hybrid inches is close to mountain inches.

Even within a single basic bike type there can be a fair amount of difference in the bottom bracket height, which directly affects standover height.

Basically, mountain bikes and road bikes have two different sizings and you need to find out the appropriate size for you in each. Hybrids seem to sometimes be sized like road bikes or like mountain bikes, but the frame geometry probably doesn't really quite match up to either style of bike and they may report the sizing as what matches the other style or as the actual measurement. There's a lot of variation in hybrid geometries because there's a lot of different sub-types of hybrid intended for different kinds of riders.

Because the manufacturers aren't consistent, you really need to try the bikes out to find the right size bike. Two bikes of the same basic type may be the exact same height but have different top-tube lengths and therefore fit you differently. If you're an experienced rider you might be able to work out what you need to know for a bike given the full geometry information that many manufacturers publish, but the single number size will never be enough.

See also: http://www.sheldonbrown.com/frame-sizing.html


If I replace the cassette on my road bike, should I replace the whole drivetrain? Relatively new to road cycling, have bought a 2nd hand bike and am thinking some parts of the drivetrain need replacing. Have tried to find this online and can't find any answers. Thanks!

If the new cassette has the same gears (# teeth) as the old one, you may not need to. If your chain is worn or in bad shape, this would be the time to replace it. If the new cassette has a different number of teeth in the larger cogs, you may need to lengthen or shorten the chain.


KMC X9 chain: can I replace some links from any chain? I've got some broken links in my KMC X9 chain. Is it possible to replace them with links from any 9 speed chain? Or do I need to replace the whole chain? Also, in that case can I just use any 9 speed chain?

The cassette is Shimano 9 speed but the chain is KMC x9 and I cant figure out which one of the KMC x9 it is. For example here it says they have like a few of them.

http://www.kmcchain.eu/chain-mtb-multispeed-9_speed

Thanks a lot

A basic 9-speed chain doesn't cost all that much so in most cases this wouldn't be worth it, especially since having several damaged links kind of implies a chain that's pretty beat up and in imminent need of replacement anyway.

But, you can do it safely if you want to. A good approach here would be to take advantage of the fact that 9-speed KMC MissingLinks are designed to be fully compatible with both Shimano and KMC 9-speed chains, which implicitly means KMC designed their 9-speed inner link thickness to exactly match Shimano. So if you're replacing a damaged segment, get a scrap of any KMC or Shimano 9-speed chain, trim it so that it's got an inner link on both ends, and use 9-speed MissingLinks to connect it. With two-piece connecting links, if it snaps together snugly such that you can't easily separate it by hand, you can be pretty confident no forces from riding will be able to separate it either.

Another approach would be using Shimano 9-speed replacement pins, and then prepping the KMC part to be inner links, since the replacement pins have to go through Shimano outer links only. This would physically go together but it would be against Shimano's warning of only connecting the "leading" link this way, supposedly for strength purposes.

SRAM 9-speed PowerLinks work the same way for most intents and purposes, and a lot of people use them without issue for any 9-speed chains.

What you shouldn't do is press a pin that's been partially driven out of a 9-speed chain back in to the outer link, because it can cause failure.


What is the widest range 9 speed cassette? My commuter rig is an old trek mountain bike that I've converted to fixed gear with an ENO hub/crankset.  I am thinking about going geared for the winter.  I have a rear wheel that I built last year and never used (found the eccentric wheel on craigslist around the same time), an SLX rear derailleur and an LX shifter.  Looking for a wide range cassette so I can take the bike offroad a bit more often, but I'm hoping to keep my 42t chainring on.  I'm willing to take the risk that the ENO ring can work with a 9 speed chain.

The best I've found is a shimano CS-HG61 (12-36) which I think would be more than enough, but if there's anything bigger available I'd like to know.  Not interested in mods/adapters.

If you are looking to go faster on the flats you can find multiple cassette models with a range of 11-34. If you are looking for more "granny" on the hills, 12-36 is the best you are going to find out of the box without swapping out the low ring. (Sheldon Brown)

That said, on most 9-speed cassettes I have seen, the smallest ring or two are not riveted to the body, so you could easily swap the 12 out for an 11 to get that much more range.


Software to evaluate *.gpx files I record my mountain bike tours using my Android mobile. Now I want to evaluate the tours. Currently I'm using MyTourbook. This would be a great software, but it has two major drawbacks: The height is calculate very roughly and the time in motion calculation isn't correct too. That's why I'm looking for a new software. The software should be able to:

Show the tour on a map
Show me the distance, the elevation, the average and max speed and the time of each tour
A little bit of statistics, so that I can see how many meters I've done in a year, a month, etc.

Any recommendations? It should be for windows.

not sure if a web "software" (aka website) is in your needs, but I recommend GPSIES: http://www.gpsies.com/convert.do

Item 1 of your list is for sure;
Item 2 not sure if it will be at such fine grain;
Item 3 yes, maybe not in such detail.

Even if not for this need the link is usefull and free, I use it a lot (I have nothing to do with this site I just like it).


Excepting the hubs, are the front and back wheel in OEM road bikes or in Road Bike wheelsets manufactured differently? Essentially I am wondering if wheelsets are manufactured differently for the front than the back wheels. I assume only the hubs and spoke holes?

Yes - they're totally different for a number of reasons.

The rear hub has a cassette on the right side, so the wheel has to be assembled dished.  So the right side spokes are slightly shorter than the left-side spokes.

Right image shows something that MTBs have tried - having the right chainstay further from the bike's centerline than the left chainstay.  This is not common on road bikes.

Rim profile can vary too.  A front wheel can be flipped and used the other way around, (with the possible exception of directional tread on a tyre, and disk brakes.)  So front wheels are built symmetrical.   Rear wheels are dished, and as a side effect the nipples can be at different angles as they leave the rim.

Here's a cross-section of a MTB wheel that shows it nicely.

The tyre is centered in its track about 2-4 millimetres to one side of where the spokes would be centered.  You can see the hole where the spokes go through, and its part-way out of the valley.  This is ONLY practical on the rear wheel and lets the builder use slightly more even spokes but still have effectively a "dished wheel"

In addition, the power of drive comes through the cassette, so the rear wheel might be laced with a variety of patterns.  Most common is 3-cross, where each spoke crosses with three other spokes on its way to the rim.  2-cross would be slightly shorter spokes.  Combinations like radial lacing on the non drive side and 2 or 3 cross are not as rare as they used to be.

Front wheel lacing seems to be favouring radial spoke design for simplicity, but that's at odds with front wheel disk brakes.  So rim-brake road bikes will move to fewer spokes radially, but disk brake road bikes will drive it back to 3-cross and add spokes.

Left wheel is radially spoked, and right wheel is 3-cross.

Spoke count matters too - the front wheel carries less load, so can "cope" with fewer spokes.  The downside is a weaker wheel, which translates to a heavier rim.

Spokes might be bladed on the front and plain old round ones on the back.  The front wheel runs in cleaner air, with more predictable aerodynamic effects.  The rear wheel is in much choppier air, so bladed spokes have less beneficial effect.

So yes the front and rear can be assembled differently.  The method to assemble them would be pretty much the same, as long as the wheelbuilder gets the crossing correct while adding spokes.  Bladed spokes provide extra challenges, but nothing a wheelbuilder can't handle.


building a cargo trike (bakfiets): steel thickness I'd like to build a "bakfiets"; a cargo-trike with the box in front.
I've found several resources, but none of them talk about the framebuilding material.
What is are my material options; steel? what thickness is best to choose? do I choose a square or U-profile.
One of the things I'm very concerned about is weight: the stronger the frame, the heavyer it will be. I can't work with aluminium.

Any advice on this?

I suggest starting with a prototype made out of square tube and old bikes, especially if this is your first framebuilding project. Square tubing is a bit easier to work with (you spend less time mitring tubes) and the goal for the prototype is that it should be easy to build. Take shortcuts, in other words. Get something you can ride, then ride it. When things break, fix them.

As far as wall thickness, I'd buy whatever is cheapest. Weight for the prototype is not critical. For a final build in chrome-moly steel the thickness will depend on tubing size and how much stress it's under. You can buy plain gauge cold drawn 4130 steel tube in a range of sizes and wall thicknesses, usually by the metre. Which ones you want will depend on the detailed design.

Groups like Atomic Zombie and a lot of HPV and velomobile enthusiasts spend a lot of time just working this way, because it's cheap so you can afford to build things just for fun.

This site shows a steel prototype long john bike built and ridden, then eventually CroMo final bike built. There's some description of the design process and you can see the idea progress from welding random bits onto a steel chassis rail through to riding the finished bike.

One note of caution: you will need to tilt the pivot axle back from vertical to get more stability, but that design is inherently unstable.


Why would a bike computer calculate distance accurately but average speed inaccurately? My otherwise reliable non-GPS bike computer calculates an extremely inaccurate average speed for my morning commutes. After my ride this morning, I read the following values from the display (units are in miles and miles per hour):

trip dist: 1.70
trip time: 00:06:29
avg speed: 16.47
max speed: 23.86

However, the actual average speed is: 1.7 / (6 / 60 + 29 / 3600) = 15.73. The reported value is off by almost 5%. This bothers me because I like to set goals to improve my average speed (for my traffic-light-enforced "interval training"), but the inaccuracy is higher than the 0.5 mph increments I reach for.

I would have assumed that a bike computer would compute average speed simply by dividing "trip dist" by "trip time"? What is it computing, and why is it different than the true average?

(slightly related: Why aren't average speeds computed over distance?)

Okay, this actually requires some knowledge of how these little computers work internally. Bicycle computers need to be extremely low-power, so the easiest way to do this is to make them very simple. Normal computers are able to use non-integer numbers. An integer is 1,2,3,4, etc., non-integer means for instance 1/2, 0.5762 or pi. Computers use so-called floating point numbers to represent non-integer numbers.

However, floating point numbers are very hard to use for these small computers compared to integers. So, they don't! They only use integers to do all necessary calculations, and with very little exceptions they are all limited to 8-bit integers. An 8-bit integer can store a value of 0-255. So, any calculation will (a) not be more precise than a whole number (e.g.: dividing 8 by 5 will yield 1 instead of 1.6 because you cannot represent numbers behind the decimal point) and (b) cannot exceed beyond the range of 0-255.

It's even worse: most bicycle computers can't even do math. Well, they can usually add and multiply, but they cannot divide or subtract. They are really super bare bones stuff, because they have to survive for a couple years on the juice in a single coin cell.

So, how does this affect the calculation of distance, speed and eventually average speed? Well, a bike computer has only 2 inputs: a very precise timer (usually outputting between 1024 and 32768 pulses per second) and a pulse input from a magnet on your wheel. It also knows how long the circumference of your wheel is. So, in order to calculate your current speed it does the following:

wait for a pulse from your wheel
start a timer
when the next wheel pulse arrives, stop the timer
divide your wheel circumference by the time and use a lookup table to convert this into something human-readable.

So, let's say the timer runs at 1024Hz and your bike wheel turns at about 5 rotations per second (36km/h or 22mph). This would mean that you would count floor(1024/5)=204 timer ticks per wheel rotation. In the little processor is a lookup table that relates those 204 ticks to your specific wheel size (which you programmed in) and then finds what speed needs to be displayed on your screen. It doesn't actually calculate it, because it's very hard for that processor to do such things. Besides, this table only needs to be a couple wheel sizes by a few tens or maybe 100 different time values. For instance a 5x100 table, pretty small in computer terms.

Distance is very easy to calculate: just multiply wheel circumference by the number of rotations. Then use another lookup table to relate this to something displayable. This too only requires a small lookup table.

However, average speed is not something that can be put into a reasonable-size lookup table. There are just too many possible trip distance and trip time values that can occur. So these computers have to cheat somehow: either they need to use the very limited math capabilities they have, or they need to round some things down or look for the nearest average value. This is exactly what your bike computer is doing.

There are more advanced bicycle computers, especially nowadays. With older designs, you could really see this lookup table-nature of operation: it could display for instance 22.3 km/h and 22.5, but not 22.4. Why? It was not in the lookup table. No matter how hard you would try to ride exactly at 22.4 km/h, it would never actually display this value. Also, older designs would only allow you to enter the inch-size of your tires, not the actual precise circumference in mm.

Nowadays, there are actually bike computers that can handle more 'complex' mathematical operations and use better number representations (either 16-bit integers or floating point numbers) to get to a better estimate of your speed and averages.


Stuck gear hub on the way into a gear on an internal geared hub My bike recently got stolen :( therefore I have borrowed a bike with an internal gear hub from my stepdad, which was working fine until recently when the pedals just wouldn't turn whenever I switched to 5th gear or higher (it has 7 in total). I seem to have inadvertently changed up to the 5th gear at some point, and from what I can feel and know I'm pretty sure the gear hub is half stuck at the entrance to the 5th gear.

It's kinda hard to explain, but the bike seems to have gotten stuck while going into the 5th gear and now when I turn it back down it only partly works. When I'm going slow with the pedals, it seems to be in 5th gear, but when I go hard on the pedals, it goes to my chosen gear, although it still does seem a bit sketchy. When I turn the pedals backwards, it seems to scratch something in the gear hub. When I go to 5th gear or higher, the pedals simply get stuck and I can't turn them.

As said, I believe the gear is simply stuck partly into the 5th one, but I would like to know if I am able to fix this by myself or with a helping hand? Me and my stepdad know a thing or two about practical stuff, but none of us have ever done anything to a gear hub before, although after googling around I think I get the concept.

It says MicroShift at the shifter, neither the hub nor the shifter have ever been taken apart, the gears were working just fine yesterday until the afternoon when I rode it to badminton.

Internal gear hubs are full of sproingy bits. This is what a Shimano gear hub looks like inside:

If that doesn't dissuade you, then you should know that Shimano doesn't generally sell replacement parts**. About the only thing that Shimano lets you do is change the oil and the bearings. If the hub is still under warranty, then Shimano will replace it in its entirety rather than trying to fix it. If it's broke out of warranty, then Shimano says: "Sorry, you should have bought a Rohloff."

** Your mileage may vary. As krzski notes, some Shimano dealers in some countries may have spare parts.

Rohloff does have replacement parts but Rohloffs rarely break. Here's one person's take-apart of a Rohloff hub:

The three-speed Sturmey Archer internal gear hubs are a bit less complex, but still I wouldn't take one apart for the lulz.

But before you give up hope, take your bike to a bike shop. It may be as simple a matter that your indicator spindle or shifter cable needs adjusting. Sheldon Brown has very good instructions on how to adjust this (e.g., for Shimano Nexus) but we'd need to know which unit you had for us to give you details here.

Update: You've clarified you have a Microshift shifter, which is commonly used on Shimano IGHs. Follow Sheldon's instructions on adjustment first before attempting repair. Another valid option is to pretend that your bike just doesn't have those gears and to live with it.


Tri-bars/Aerobars on Mountain Bikes I am trying to work on endurance in the hopes of one day touring the GDMBR in a reasonable amount of time and after watching Ride the Divide, I noticed a lot of the riders are using aerobars. When I am training, I can ride close to 40 miles on my bike with a Specialized flat bar but I am noticing significant pain in my back, tailbone, wrists and shoulders.
Are aerobars the answer to my pain problems? My assumption (from purely a comfort viewpoint) is that aerobars allow you to shift your weight occasionally and distribute your weight differently without stopping. If so, is there a certain type of handlebar I should be looking at for a mountain bike? I would prefer an easy to install/uninstall solution because I am not always looking to have these handlebars on. Also, is adding an aerobar the proper solution or am I looking at it wrong? I am questioning bikes at the moment and would be grateful on any tips.
I have never used any other type of handlebar other than a flat bar, so please include anything that may seem incredibly obvious.
Note: I looked at this answer but those look incredibly uncomfortable for long distances and seem pointless for what I am doing.

Specifications
Bike
Specialized Myka Sport 29er
Handle Bar Specs
Specialized flat bar, alloy, 640mm & 660mm wide, 8-degree backsweep, 4-degree upsweep, 25.4mm
Full Specifications

The main reason that aerobars may have an advantage over flat or road bars is that they are designed so that your main support mechanism is skeletal, rather than muscular. The longer the distance, the more this will hold true.

This picture is of a top triathlete. Note that the forearms are almost parallel, and the upper arms are at a 90 degree angle. This allows the main support for the upper body to rest on the bone structure, with minimal muscle involvement. (Stadler was an Ironman distance triathlete, bike segment of 112 miles).

While you may see variations on this, it is a general truism that the longer the race, the more comfort trumps aerodynamics, and vice versa (Short races aerodynamics trumps comfort.)

Many of the ultra mountain bike competitors set up their rides similarly, and have "wrap" style aerobars that allow them multiple different hand positions for control, as well as the resting position where their arm muscles don't have to do the work for support.

That all being said, I would point out that many riders go much further than 40 miles with no pain at all. This would suggest to me that your fit is not correct, or that you are not in shape enough for a 40 mile ride yet. Tailbone pain is (usually) a bad saddle and fit, and the rest is also easily attributable to fit. Aerobars will not be a magic cureall for an improperly fitted bike


Is this road/city frankenbike concept a feasible idea? I do a half-hour each way city commute every day and the Yepp EasyFit mount I just installed on the rear rack of my already over-optioned Vanmoof 5.1 is the straw that broke the camel's back. In addition to the front carrier, integrated chain and SRAM Automatix hub it's just too heavy. I can barely lift the thing.

I need a lighter bike.

But I do like some of the features of the Vanmoof:

Un-stealable, always charged, ridiculously bright, hub dynamo powered lights
Rust-free, "natural" don't-care-if-it-gets-scratched aluminium frame
The lock integrated into the top tube—easy and quick to lock and unlock, even wearing thick gloves
Low-maintenance straight chainline (I detest  derailleurs)
Dutch-style upright riding position
Mudguards and chain guard–I ride to work on the thing and I'm not interested in changing clothes to ride

I'm tossing around the idea of building up a custom city bike, starting with something like a Surly cyclocross frame and a NuVinci rear hub (I have one on a bakfiets and love it), with the Yepp Easyfit rear rack on the back and some kind of basket on the front. Add mudguards and some kind of lighting system and I have a bike that's light and fast when I want it to be but still capable of doing the preschool or shopping run.

Is this remotely feasible?
Any recommendations on hub-dynamo powered lights and how to mount them to this kind of frame?
What do I do about locking the thing and retaining at least some of the advantages of the built-in lock on the Vanmoof?
What kind of brake system might be appropriate, and compatible with the NuVinci on this type of frame?
Tyre recommendations (Thickslicks be good?)
Are there any non-janky mudguards and chain guards that will fit this setup?

I think your idea is sound, a lighter alloy frame, with decent tyre clearances to allow the comfier larger tyres.

Hub dynamos go in the front of any standard wheel.  There's nothing particularly special, as long as the axle mounts suit the frame's fork.  That's probably nuts and bolts, rather than a QR or other quick removable fastening.  Also wires - you'll probably end up with externally routed power cables because internally routed ones would be hard to retrofit.
Lock - I am unfamiliar with the lock, but based on this image its just a chain in a tube that is fastened to the bike permanently, but offers no protection to the wheels.  Its an abus lock, just buy one of similar size and carry it in your basket.

Brakes - you'll need two independent brakes, one on each wheel.  Whether you go disk or caliper or canti or V brake will depend totally on what mounting bosses are on your frame.  That will dictate whether your wheels need a brake track or a rotor mount.  A CX frame will probably be cantilevers unless its from the last couple years.
Tyres - thickslicks are susceptible to punctures.  I have a lightly set laying around and haven't found someone I hate yet to off-load them to.  Based on the lock pic, the default tyres are fairly large.  You want to keep that sizing or similar.
Chainguards - ugly things.  Consider a belt drive instead, which will be a fair match for your IGH.
Mudguards/fenders - they're all a bit large, because they have to sit close to the tyre and cover at least as wide as the tyre.  Mudguards also should go quite low behind both wheel, so you're stuck with at least 1/4 to 1/3 of the circumference on the front, and a bit over 1/2 a circumference on the back.

Alternative idea #1   Since you like basically everything about the vanmoof, consider checking their current lineup for a model more to your current requirements.    Their website doesn't list weights, but some resellers might.

Alternative idea #2   Strip the usable bits off your current bike and fit them to a replacement frame that suits you.    Its an option, but I'd suggest your existing bike has a value and can be sold on to fund the new one.


How popular is the "Sold Secure" certification among reasonable-quality lock makers? I'm a recent convert to cycling, having moved to Amsterdam, and I intend to buy a U-lock for a bike I'm getting.

Now, people have recommended that I buy U-locks with a "sold secure" label - but in a couple of bike shops I've been to I haven't seen any items with this label. Granted, there wasn't that much variety, but it did make me wonder - is that certification very popular with lock manufacturers (of reasonable-quality locks)? Or is it more so for manufacturers in other countries than here? I need to decide whether to limit myself to locks with the certification or think of some other way to evaluate locks.

You might have a bit more luck doing things the other way around - go to the Sold Secure web site and read off a list of compliant locks. When I was buying, I took this approach, chose the locks and then bought them online.

Also, bear in mind that Sold Secure originated in the UK, so possibly lock manufacturers who sell mostly outside of the UK market might not consider it worthwhile to worry about this badge. But having said that, I can see right now the Sold Secure sticker on both Kryptonite and Abus web sites (two of the biggest names, neither UK-based) against certain of their locks.

As regards how useful the Sold Secure branding is, you should be aware that this is pretty debatable. I've heard the scheme described as a marketing scam by the insurance/lock industries.

That having been said, I have a bike insurance policy which specifies that I need such-and-such a grade of Sold Secure lock in order for the policy to be valid. So, putting aside the issue of how "good" the lock is (in terms of protection against theft), in terms of me complying with the insurance policy it is a no-brainer just to use a lock with this badge on it.

Note that Sold Secure also have a scheme that applies to motorcycle locks, if that helps you to find a stockist. I have a chain which is rated as "silver" for a motorbike, but "gold" for a bicycle.


Preparing for long term storage (2 years) I have two bicycles - one is an alloy MTB and the other is an old steel frame roadie. I intend to box them and keep them in my parent's garage for the next ~2 years while I will be overseas for work. Selling is not an option (for emotional and real value). I plan to box both bikes as they come from the manufacturer:

pedals, handlebar, chain and seat off
Rear derailer removed, wrapped in bubble-wrap and tied to the frame
Current tires will be sold off and an old useless pair installed with old tubes nicely coated with talc to keep them from becoming sticky.
Healthy doses of lube on the cables
Plastic wrapping on the MTB brake discs, spacers in the calipers.
Box taped down with lots of duct tape.

Storage tempeatures will be from 5C to 45C during the year, and humidity will be low-moderate most of the year. Is the above scheme adequate? Anything else I should look out for?
Update: Thanks for all the pointers. One point I forgot to mention is that the bikes need to be shipped from my current residence to my parents first. The overkill packing is intended to ensure that they survive the transport and also the boxes can just be stowed till I get back, requiring no attention.
Update2: 4 years later
Due to multiple reasons, latest being the Coronavirus pandemic, the bikes have stayed boxed for 4 years almost to the day. I'll be getting them soon and will update this thread soon.

Your plan sounds pretty sane to me.

Depending on how tolerant your parents are, I would prefer to leave the bike intact and open to the air, so it can dry if it gets damp, but that may not be possible.

I returned from uni, a long time ago now, and dug out my old mountain bike. It hadn't been prepared for 3 years on its own but came out just fine, less a few parts my brother had relieved me of.

When you return you'll want to give them a pretty through service but over 2 years nothing much should have degraded.

Tires would most likely be fine, if they're tubeless the sealant will have dried out and either disappeared or formed a lump of goo. They'll be flat and may crack along the fold.

Some bolts will have some surface rust.


When to use coaster brake, and when to use rear rim brake? I have recently moved to Germany (from the UK) and started commuting to work by bike. Apart from the confusion of cycling on the other side of the road, and the levers for the brakes being the other way round to the are in the UK, my new bike is fitted with a coaster brake as well as calliper rim brakes for the front and rear wheels.

I have never ridden a bike with a coaster brake before, as they are unusual in the UK. I am unclear as to when I should use the coaster brake and when I should prefer using the rim brake for the rear wheel? Are they essentially equivalent and I should just use whichever I find easier, or are there circumstances under which I should favour one or the other or even both together?

If it makes a difference my route to work is fairly flat and mostly consists of cycle paths separated from the road, although at this time of year there are a lot of wet leaves on which I'm finding it difficult to control the speed as easily as I'd like. It has been several years since I have ridden a bike.

The coaster brake is the primary brake. It should be used as your first means of stopping. Rim brakes on coaster brake bikes are typically a safety design. If the chain were to break or come off the sprocket you would have no coaster brakes. In the U.S. the hand brake is normally installed on the front wheel. The front wheel provides more braking power as you weight shifts forward.


Is it possible to replace bearings in Shimano XT bottom bracket cups? Curious if I can just replace the bearings in my existing cups or if I would need to buy new cups?

If possible to replace them then what are possible high quality replacement bearings?

It isn't recommended by Shimano, but some shops use a bearing puller to slide them out of the bottom bracket. I don't know if Park Tool makes one, but you should be able to find one at a specialty hardware store. Once you get them out, you can service or replace them.


Is klunking the father of mountain biking? Is attacking downhills with coaster brakes where the sport of downhill mountain biking originated? Or did mountain biking and klunking grow up side by side?

Klunker as a term is synonymous with early mountain bike (as it is currently known). Klunkers were developed by customising early beach cruisers on 26" wheels (Schwinn predominantly) by spreading the rear dropouts to make them multi-geared and adding moto handle bars and brakes due to their durability and strength (brands such as Magura were initially moto brands).

The term klunker was used to describe these built up bikes on cruiser frames.

This style of bike and mountain riding first appeared in Marin County, California in the mid 70's prior to the first purpose designed mountain bike appearing in 78. If you look at the proponents of the early mountain biking movement and design; Gary Fisher, Joe Breeze, Charlie Kelly, Tom Ritchey and Keith Bontrager (there are going to be many more....) all were active in Marin and it's surrounding counties at the time.


What is the name of the part, often seen on BMX bicycles, that allows an additional rider on the back the bike? What is the name of the part, often seen on BMX bicycles, that allows an additional rider on the back the bike? It appears to be a set of relatively short but thick poles that go on either side of the axle of the rear wheel so a passenger can stand on it and—holding onto the shoulders of the driver—can be transported with minimal effort.

What is that part called?

They are called Pegs.
Pegs are mainly used by BMX riders to help perform various tricks.
Flatland trick (standing with all of his weight on one peg, not damaging anything):

Grinding a wall on the rear peg (imagine the forces when the rider jumps on the wall, still: no damage to the hub but of course to the peg and the wall):

Images from Wikimedia Commons


Does Shimano cassette tool work on Campy cassette? I have a Campagnolo 10-speed cassette on the way, and I just want to know if I'll need a new cassette lockring tool to install it. I already have the tool for Shimano/Sram cassettes. In the pictures I looked at, the splines on the lockring look similar, but not quite the same:

-- EDIT --

This is the tool I have. And this is the tool I'm supposed to have. The splines may have fit, except the diameter is off by 0.6 mm, which sounds like just enough to make it incompatible. So I guess the answer's no. Damn Campagnolo, always making things harder...

For the record, I just got the cassette, and the Shimano tool definitely does not fit.


Why is part of this Derailleur loose? (Sun Tour Cyclone II) As you can see from this picture, part of my Derailleur  is loose.  Notice how the gear is not in flush with the cylinder.

It has a no other parts (that I can find!) than a threaded screw to go in there, but the screw bottoms out or at least seems to before it pulls the assembly in tight.

The screw itself is not of such diameter that it would hold the device in place, and while the geared part is secured by a metal lip on the side of the gear when you push it in place... the screw doesn't do the job.

This is my first time working Derailleur system.  I have no idea what part I'm missing.  I'd appreciate anybody who could tell me what it is I need..

Oh, and for the record.  This is the image of what the thing hooks onto.

It is hard to give you the exact reasons why this is happening, but your derailleur body lost a good mechanic connection with the cage. Maybe the screw that holds them has just became loose, or maybe it has gone bad, or maybe your derailleur is just old. Hard to tell from the pictures.
I don't want to be pessimistic, but repair will be hard, as manuals and parts are hard to find, and I suspect even if you successfully do it there will still be too much slack for this part to perform adequately.
It sure doesn't hurt to try. The only link I can point you to is for an overhaul of a Shimano derailleur, here. These components aren't too different and this should give you a help.
In the meanwhile, I would start putting some money on the side for a new one, the good news are that if you can't fix yours you can get something really cheap. If you ride a lot, it is better to invest in something a little bit better.
Good luck!


Squelching noise from back wheel My bike is making a weird squelching sound from the back wheel. Any idea what it might be? I made a video of the sound, it's at this link: https://drive.google.com/file/d/1zt_DAa2avX9bhJ4E-moLFJ69TSYnb2uC/view?usp=sharing

Summarising comments:

the noise is in the rear wheel
frequency is linked to wheel/road speed and not chain speed because noise continues when coasting,
noise does not change when the rear coaster brake is applied
noise only appears when bike is loaded, not walked
there is nothing rubbing on the tyre

It sounds from the audio like the tyre is rubbing somewhere. The sound is certainly related to the wheel because the frequency speeds up and slows down with bike speed, not pedalling.

You say the tyre isn't rubbing, but the sound doesn't happen when bike is unloaded, so perhaps when it is fully loaded, the frame is flexing enough to cause a rub - is there any point like behind the downtube or close to a mudguard or chain stay where the tyre is close to something? Then when it is loaded up it is able to rub.

It's also making the noise once per revolution of something (the wheel) so something is out of balance. Maybe the wheel isn't true, radially or laterally, or the tyre is bulging at one point on its circumference.


What's the idea behind the no-feeding-in-the-last-20-km rule? I'm trying to understand the reasoning behind the no-feeding in the last 20 km rule. In the Tour de France 2020 Julian Alaphilippe lost his lead due to an infraction of this rule.
Might it be:

The competitors are in full sprint. It's too risky to be distracted by using one hand for food/drink.
It's unhealthy for the competitors, since for the food to be beneficial, it'll have to be pure glucose. There is too little time left to digest anything more complex, and if they don't get it exactly right, they could "hit the wall".
Food in the last stretch starts to act as a deciding factor. A team that discovers a concoction that provides an unfair advantage would win based purely on that food/drink, not the ability of the racers.

I'm sure the reasoning is well established. Is it also well known? More personally, does the rule matter for the amateur? Is there any reason why an amateur should not eat/drink in the last ~20% (if not 20 km) of a trip?
Update:

(The following thought emerges from Vladimir's and Weiwen's answers.) Might I have been sloppily confusing the verbs "feeding" and "feeding oneself", and might the rule be more easily expressible in the precision of French's distinction between reflexive and non-reflexive verbs? In other words, it is perfectly allowed to feed oneself ("se nourir") during the last 20 km. What's not allowed is to give (or take) food from someone else ("nourir"). The rule would be clearer if we start to split hairs and ask whether it's allowed for a helper ("domestique") to pass some food to a hungry (and more important) team leader during the last 20 km.

Gratuitous and unrelated comment/question, now that I'm noticing that all the cars clear out during the last 20 km: How do the cyclists tolerate inhaling the exhaust of so many cars during the race until the 20-km mark? It's one thing for a (gasoline) car to pass by; it's another to remain behind it—inhaling the discernibly worse air—for hours on end.

If you do not race in a UCI  race you do not care about this rule at all. If you are thirsty, you drink. The end of the trip is where you are at the greatest danger of bonking so if you feel hungry or weak, just eat or get some quick sugar.
Actually, the racers can also do so, but they cannot get new food and new water, they only can use what they have.
UCI Rule 18:
"All feeding (from a car and on foot outside of the feeding zones signposted by the organiser) is strictly forbidden: during the 30 first and last 20 kilometres; ..."
If you are just eating your own food or drinking your own water, you are not acting against any imaginary rule on your trips.
I do not think any of the reasons you list is exactly the right one. The closest one would be number 1, but not literally. They are not in full sprint, but disruptions and distractions have to be prevented at some point. And by default that point is 20 km. Sometimes it is postponed when the weather is hot.

Reaction to the update:
I do not think that passing a bottle from a domestique to the leader is forbidden, but I am not sure. It does not appear to be against the wording. I really do think the rule is to prevent the distractions from team cars and from riders moving to the side of the road in the deciding parts of the race. The wording appears to be clearly against external feeding and not against feeding yourself at all.


Updating brakes on a vintage tandem I have a 25 year old Colnago road tandem on which  I would like to update the brakes.

The problem I am having is that they are 27" rims and I can't find a proper brake setup that will work.

What brakes will work best?

Here's the sole Colnago road tandem picture I could find anywhere.

Is your bike anything like this ?

From http://www.ebay.com/itm/Colnago-Tandem-Bike-X-Campagnolo-Groupset-Pantographed-Vintage-Very-Rare-/151292492125?hash=item2339bc395d&pt=LH_DefaultDomain_0&nma=true&si=3DCdggTFjbiHTJYmI3jOxvB%252FJrE%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557
and there are more photos there.

If so - it has single pivot caliper brakes, and definitely steel rims.

Your first bet would be to swap out the brake pads.  Then change all the brake cables, both inners and outers.  These are both maintenance tasks and do not detract from the bike.

Replacing the single pivot with dual pivots would help, but finding something period might be difficult.  IMO safety is more important than originality, but others disagree.

Finally, steel rims tend to be poor at braking anytime.  If you can find some 700c alloy rims, they will brake much better.  Downside is they're fractionally smaller than 27" wheels, so you'll need new tyres and tubes, and the brake calipers will need to reach further, which can compromise their effectiveness.


HED Tomcat disc, 24h, 21mm internal width What's the smallest size tire that will fit these rims: HED Tomcat disc, 24h, 21mm internal width

Welcome to StackExchange Bicycles.

That is a good question - and one that is answered very well already in this post: What is the maximum or minimum tire width I can fit on my bicycle
.  Have a look at that and see if it helps.