What is the weight limit for a Cube Aim Pro 2021? My Cube Aim Pro 2021 model is being delivered this upcoming Saturday. I'm really happy about it because there was a huge run on mountain bikes, it will be my first.
Now my concern is I'm quite heavy (119kg) and this PDF file says for my hardtail Aim (I got the Pro but that one is not on the list) that a rider weight + bike weight should be not more than 115kg, so I'm way over that.  But on the right it says that the weight limit is 140kg (then I should be good right?)
Now I'm wondering, what is it? And yes I know I'm way too heavy but that's why I'm getting an MTB, I'm going to start with riding gravel roads, no jumps or anything (I live in the Netherlands).
Should I just cancel the whole bike or just ride it? I'm really not sure if it's 115kg max or 140kg max.

Okay! I will only be adding a front and back mudguard, for the rest I won't be adding anything. The 115 is for the bike+rider and the extra 25kg is for lets say a backpack or a kickstand? And that makes 140kg but I wont be adding any cargo backpack or kickstand, only the mudguards.
What would you do? Cancel the bike or just use it because I don't want to destroy it in like a month of riding.

From personal experience: The #1 thing you're going to 'destroy in like a month of riding trails' as a heavier rider is the rear wheel.  As soon as one spoke gets a bit out of tolerance the whole thing starts to come apart and go wildly out of true very quickly.
The frame might only last 7 years instead of 10, maybe crank arms and spindle will wear out in 3 years instead of 4 etc etc. but it's almost certainly the 32H rear wheel that is driving the uniform 115kg stated rider+bike limit across the entire product line of different types of frames.
A mid-range Cube would seem to be in the range where it's "worth" upgrading with a sturdier 36H wheel and would still come out cheaper than a specialty bike like a Surly that comes with them standard.  (and one assumes decent wheel builders aren't that hard to find in the Netherlands...)
(You may also just get the stock wheel re-laced with sturdier spokes, but if you're paying all that labor to have it re-laced anyway, the hub and rim aren't super expensive...)


Front wheel Fork is having scratches and Oil is getting leaked from it? I thought that it might be a fault of Oil seal but Mechanic was telling that I have to replace both the fork If I replace only the Oil & Oil seal then again It will leak oil.

Is it a dangerous problem and should I replace both the forks?

Below is an image found on this blog
http://thegoldenwrench.blogspot.in/2012/04/same-sad-story.html

Thanks.

That stanchion is stuffed and needs to be replaced.  If the damage is from normal wear and tear the other will need replacement - probably cheaper to get a whole new fork. If its accident damage (e.g from rubbing while on a car rack) and the other is in very good condition, replacing the damaged one is an option (if you can find a single replacement).

Replacing the oil will buy you a couple of rides and a mess to clean up at the end of each one, and the shock will not perform particularly well.

Its not really a dangerous problem, but the fork will not be working properly and will sag under load.


Cage Length (Rear Derallieur) and Total Capacity My drivetrain required total capacity is 14.

(folding bicycle Dahon Eco C6, 14-28 rear, 1x front)

The rear derailleur (Shimano TZ50, which I purchased), has total capacity = 34 and a long cage. Are there are any disadvantages, in such overkill, when total capacity of the derailleur (34) is much higher than required (14).

There's a huge disadvantage for a Dahon and any other small-wheeled derailer bike, which is that the cage is gong to be unfortunately close to the ground no matter what you do, and having a longer cage than necessary makes the problem worse.

Shorter cages also manage chain slap better and are lighter.


Triple chainring + nonstandard sloped cogset. Can this work? It seems that on my mountain bike and all other multispeed bikes I have seen having a rear cassette or freewheel all have sloped cogs, meaning they go from largest to smallest in order of decreasing size (such as 28,24,22,20,18,16, and 14 in my case).  Problem is that basically creates a triple range 7 speed, not really a 21 speed.  Also some combinations are not recommended cuz of a diagonal chain and some are duplicates normally and many combinations are very close so they are not really a unique gear ratio.  Also, to get progressive gearing, the rider has to shift in a funky order to get increasing gear ratios.

To help alleviate these, I had an idea but not sure if it would work.  Basically you would still have a triple chainring but 9 cogs in the back.  The idea is you use 3 cogs with each chainring.  So chainring A (the granny gear) only engages cogs 1,2, and 3 (the 3 largest cogs).  Then when shifting to gear 4, you shift to chainring B (the middle size chainring) and cog # 4.  Here is the variation though.  Since the front chainrings might be 24,32,40 and assuming the rear cogs are 28,24,22,20,18,16,14, we would be jumping from 24/22 = 1.09 to 32/20 = 1.60 which is a huge jump.  To help alleviate this I was wondering if the rear cogs can be "staggered" such that even with the larger chainring every 3 gears, the overall gearing would be progressive and consistent (no big jumps).  For example, 3rd gear can be 24/22 which is about 1.09 and 4th gear could be 32/25 which is 1.28.  So when shifting from 3rd gear to 4th gear, the front chainring size goes up 8 teeth but the rear cog also goes up 3 teeth, thus eliminating the large change in ratio and making it more mild.  So the 3+9 setup would effectively be a true progressive 9 speed bike but with better chain alignment than a 1x9 setup since the front 3 chainrings would be aligned with cogs 2,5, and 8, thus never being misaligned more than about 1 chain width so the chain will be almost always straight (not diagonal).

So my question is can a rear cassette have cogs like this that are not sloped all the same such as 28,24,22,25...?  Will it shift ok or are cogs only designed to be "progressively sloped" and not mixed like in my idea?

Addendum: Also with my idea, it would allow 12 speed cassettes since each front chainring could engage 4 rear cogs.  The front chainrings could be aligned with cogs 2.5, 6.5, and 10.5, thus never being misaligned more than about 1.5 chainwidths.  A progressive 12 speed could have both reasonably close gear ratios and wide range.  My ideal overall range for a bike (to cover almost all circumstances) would be 0.5 for the low gear (13 gear inches for a 26" rear tire) up to 4.0 (104 gear inches for 26" rear tire).  I could design a 12 speed to cover that range.  It would require about 20% change in each successive gear unless you had a big jump for the lowest gear, then you could slightly tighten up the other gears to perhaps 18% or so.

Yes, you could do this and done as you describe I think you'd end up with as many ratios as rear cogs.

Someone once made a single-shifter derailleur system that moved both derailleurs from one shifter (using two cables) and "IXOV" has apparently started doing that again with the "Synchrobox" but all I can find are press releases, not even a company website. They typically use fewer than the maximum number of gears because of the overlaps, but from memory they do give more than just one gear per rear cog.

If you were building a bike this way you might be able to get away with minor back-jumps (a cassette that went 12,13,14,15,13,18,21, say). You might even be able do use a normal shifter with it by using a lever attached to the cable to shift the front derailleur some fraction of the movement of the rear one, but I suspect that would not work very well. If you used a cam instead you could get the larger movements for chainring shifts where you wanted them, but it would be a more complex design.

Using that diagram above to help me think, if you had a 9 speed close ratio road cassette you'd have three gears per chainring:

chainring / cog = ratio

9 speed 12-23            10 speed 12-30

44 / 12   =  3.67        44 / 12   =  3.67
44 / 13   =  3.38        44 / 13   =  3.38
44 / 14   =  3.14        44 / 14   =  3.14
34 / 15   =  2.27        34 / 15   =  2.27
34 / 16   =  2.13        34 / 17   =  2.00
34 / 17   =  2.00        34 / 19   =  1.79
24 / 19   =  1.26        24 / 21   =  1.14
24 / 21   =  1.14        24 / 24   =  1.00
24 / 23   =  1.04        24 / 27   =  0.89
                         24 / 30   =  0.80

That doesn't work too badly, graphed it looks like this:

With a 10 speed 12-30 cassette that also works:


Which bike light, aren't that to be seen kind enought? I just bought a giant escape 2 and have been using it to go to work. When is time to come back home is already dark and I'm planning to get a light. Asked about one in nearby bike shop and they suggested me the following (https://www.qoo10.sg/item/GENUINE-GIANT-ZOOM-LIGHT-BICYCLE-LIGHT-HEADLIGHT-LIGHT-TORCH/531628737):

Comparing it to the models from Giant website https://www.giant-bicycles.com/us/lights it seems to be on the cheap side.
I also noticed they classify lights as "to be seen" (cheap, i.e. hl100, hl200) and "to see" (expensive, i.e. hl500).
So which one would you advise me to get? If hl100 is not enough perhaps hl200 is ok, or I better go with the hl500? In principle my intent is to use the light to see.

So you're riding at night - are the routes lit by streetlights?  Or are you riding in pitch darkness?
The former would recommend two "be seen" lights for the front and two for the rear, and the latter would require at least one Seeing light and a backup for the front and still two on the rear.
I'd strongly recommend adding some combination of spoke reflectors, reflective sidewalls, and reflective clothing to go along with your active lighting.   DOT tape is available in appropriate colours and costs nothing to operate.
Be aware you do not need a Giant-brand of light on your Giant branded bike.  The only time such a thing is needed is if there are built in connectors to an internal wiring harness or similar.  Otherwise you're free to fit whatever lights you like.
I personally run two completely different front lights plus a head lamp.  The main one has an "hours remaining" readout which tells me if I can make it home before it goes flat.  Likewise I have several rear lights each with their own power, so they're less likely to all go out at once.


Is there any replacement for the chainrings of a Shimano STX crankset? I have a Shimano STX Crankset (probably FC-MC series or similar, around 2001) with worn out chainrings (5 Arms). Is there any contemporary replacement opportunity for either the chainrings or the whole crankset?

Just look for any chainrings that have the same bolt circle diameter, the same number of bolts, and are designed for the same number of gears that you currently have and you'll be fine.

Although you may find that it's cheaper to simply replace the whole crankset than to buy individual chainrings.


Is there a way to check for non-visible damage on a carbon frame? I had an accident on my carbon road bike. As I look at it, I do not see visible damage to the frame or forks. Is there a way that the frame can be tested for damage and if so, how do I get this testing done?

I've heard of people having their frames x-rayed, but for obvious reasons that's not very practical. The most reliable manner of checking a carbon frame for damage that I'm aware of is the old coin tap test. Get a quarter ( or whatever coin fits that form factor in your local currency) and go over the frame lightly tapping the edge of the coin against the frame. Intact carbon makes a distinct "clack", whereas damaged, delaminating carbon will have a much duller thud sound when tapped. Keep in mind that as the tubes change shapes and thicknesses the sound will gradually change. What you're looking for is a distinctly different muted report that abruptly changes within a very localized area.
Keep in mind that this is not a foolproof or exhaustive method of checking your frame and fork for damage, but it does work surprisingly well. I've found many a damaged frame this way.


Damaged rim or just the tube valve? I had a flat on the way to work today.  Not really earth shattering, it was about 5 miles in, only a short walk until the office, where I could fix it in comfort.

But walking the bike, I noticed an odd behaviour.  The flat was on the front wheel, and I noticed that once per revolution, the handlebars would turn slightly to the left.  Very consistent, just as the valve would get to the bottom of the wheel.

What would cause this?  Is it just the valve being slightly thicker than the (now deflated) tube, or did I somehow damage my rim in the short while between the puncture and me stopping the bike?

It's possible you damaged your rim, but it should be very easy to check. Turn the bike over and spin the wheel and eyeball it both side to side and up and down. If you have put a flat spot in the rim it should be very noticeable.

It's more likely that it is just the way the (flat) tyre is sitting on the rim, which might well be affected by the valve. If you've got a narrow tyre and a lockring on the valve, that may be holding the tyre on the rim at that point only, causing a wobble when that part of the wheels hits the ground.


BSO identification for amateurs I'm a biking amateur, but I've been wanting to upgrade and get more serious.  Just recently, I was gifted a pretty new bike and I'm wanting to figure out how BSO it is so I can either upgrade it or get rid of it get a new, nicer bike.

What should I check to tell how much of this bike is cheap BSO material and how much will last?

I'd really like a part-by-part list so I can replace them or decide if it's not worth it.

It used to be easier to tell BSOs from "real" bikes, but now the technology is changing so rapidly, and it's much harder.

On a bike older than about 20 years, one would first look at the frame, in two places:

The joints.  Better quality frames would be "lugged", with the steel tubes brazed into fittings (called lugs) that secured the joints.  Cheap frames would just have the tubes welded together.  (Welding, as used then, would destroy the thin, high-strength steel used in better frames.)
The dropouts.  Cheap frames would have rear dropouts that were quite clearly just stamped from sheet metal, while the front dropouts would be similar, or would simply be slots cut in the ends of the flattened fork tubes.  Better quality would use forged dropouts.

These days the dropouts are still a tell, but not nearly as reliable as before.  And frames are often made of materials other than steel, and even steel can now be welded, using a rapid-weld process originally developed for aluminum frames.  (Though a good-quality lugged steel frame is still a thing of beauty.)

Other than the frame, the most obvious identifier of low quality is a one-piece crank.  This was true 20 years ago and is still true.

Well, I'll take that back -- one more thing:  Twist shifters are highly suspect.  They are cheap and have an extraordinarily high failure rate.  There presumably are some good quality twist shifters, but they're the exception.

Make that two more things:  With a multi-speed bottom bracket, check the material used to make the chainrings.  Very often BSOs have steel rather than aluminum chainrings.  A better quality bike may have a steel "granny" ring, but the others would be aluminum.


Replacing front chainring on my old bike I have an old Giant Peloton Lite. Certainly considering its age, it's a very nice bike. The front chain ring is a bit worn out, however, and I'm looking to replace it.
I have a few questions about that:

It seems like a relatively easy job. Screw the old one loose, put the new one on. I've seen a video about it, which seemed to confirm that. I like doing small maintenance, so I like to do things myself if possible (instead of taking it to the local bike shop). Is this true, or is it really something I should have my LBS do?
As for parts: my current ring is a 53-teeth, I found a 50-teeth in the same make. Can I use that, or will that give me unforeseen issues?
In general, what are things to look out for in chainrings? I'm very new in learning about these things, so I'm curious what are the relevant factors determining my bike's compatability with a given chainring. The chain, for sure. But can one match a chain ring with a very different cassette or freewheel, provided they run on the same type of chain?
It is generally recommended to change the cassette (or freewheel) if  you are changing the front ring. Is that really necessary? The freewheel is still really good.

I know these might sound like naive questions, but, I'm learning and having fun doing that. Thanks for your help.
(To further specify: it's a 2x6 Exage 500 drivetrain)

Chainring replacement is pretty easy. It's easier if you take the crank out of the bike but you may be able to get the rings over the spider and crank arm without removing the crank.
You can find instruction videos for pretty much every bike wrenching task. Here is one for chainrings.Note you will need a special chainring bolt tool to fit in the long thin slot on the back of the chainring bolts.
Just get a replacement chainring from a known 3rd party manufacturer, these are not hard to find in the major online bike component stores. You obviously need a ring that has the correct bolt circle diameter (BCD) and bolt pattern.
If you have 53/39 chainrings and you should replace them with the same size. 50 tooth rings are designed to be used on compact chainrings with a 34 tooth small ring. If you fit a 50 tooth you'll have a large reduction in gear ratios on the big ring and a smaller ratio gap between the big and small rings. Older cranks with 130mm BCD won't take small rings smaller than 39 teeth.
Sprocket and chainring wear is accelerated by worn chain 'stretch' (the bushings wear allowing each link to move slightly further apart from its neighbors). If you have worn you chainring out chances are your chain and sprockets are worn too. It's a good idea to replace the freewheel, both rings and chain all together. A worn chain on new sprockets or rings has a tendency to slip over the teeth.


Incompatible front derailleur/crankset? I recently bought a Tandem from the 90's and now trying to adjust the derailleurs. But, no matter what I do, I don't manage to properly set up the 3-way front derailleur. It either

properly shifts from lowest to 2nd or
properly shifts from 2nd to highest.

I noticed that the crank and chainwheels don't seem to fit to the rest. The front/rear rear-derailleur and the captain crankset are a black and Shimano Deore LX FC-M563 to my best guess, while the stroker crankset is silver and some "Shimano" which I cannot further specify.

I am therefore wondering if that could be the reason for the derailleur not working properly. Or should one-shimano-fit-all, no matter which model?

I also noticed that the chainwheels seem to be not equally spaced. It's ~8mm from lowest to 2nd and ~5mm from 2nd to highest. As far as I can tell, on all my other bikes the spacing is equal and ~5mm.
Are there such 'weird' cranksets or has it just been incorrectly assembled? i.e. could I possibly fix my problem by exchanging some spacers instead of buying a new crankset?

First of all, IMHO, when you buy an old bike you should always change inner and outer cables (cable housing) for the brakes and shifters. This will ensure that the cables have low friction and won't get stuck somewhere

Then this part "It's ~8mm from lowest to 2nd and ~5mm from 2nd to highest" makes me think that someone got the order wrong. I think the highest and the middle sprocket are on the wrong side or the crank(outer side). Or the smallest sprocket has spacers that shouldn't be there. Or maybe the middle one is lacking spacers.

99/100 Sprockets are equally spaced, because that's the way the shifter handle pulls.

Lastly, check the "front" dereaullier alingment. It should be parallel to the sprockets.


how much of a difference does bike weight make when trying to maximize the bike's top speed? Today I was at a bike shop looking at single speed bikes. I rode one, but didn't buy it because I like to bike fast, and this bike must have weighed 2x more than my aluminum road bike (the bike was steel).

The store owner told me that the bike weight will not have as great of an effect on my top speed as many other things both on the bike and things I could change about how I ride.

Is he right or wrong? Does bike weight make a big difference or is it just very good marketing?

The weight of a bike has virtually no effect top speed. It takes very nearly the same amount of effort to maintain a speed of 30 mph on a 20 lb bike and a 30 lb bike on flat ground. The biggest factors that come into play at high speeds are aerodynamics and rolling resistance ( slick, efficient tires ).

http://velonews.competitor.com/2012/05/bikes-and-tech/technical-faq/tech-faq-does-bike-weight-matter_220429

That said, is top speed what you're really worried about? Probably not. Even if you like to bike fast, I truly, truly doubt you should be concerned with top speed. You'll probably enjoy a bike that accelerates quickly and feels nimble. Unless you live in a flat, remote area, in which case you probably wouldn't want a single speed, you're probably going to be accelerating and maneuvering more than you are achieving top speed. And again, these factors don't necessarily correlate with the weight of the bike.


FSA Gossamer Crank Spider cracked I've got an FSA Gossamer pro MegaExo compact crank set.  Lately, while tightening the bolts on the crank spider, it cracked (see picture).  I know FSA has recalled the left crank because it turned out to crack for the same reason.  Has anyone had the same problem with his right crank?  Does FSA sell spare parts?

You're better off getting on the phone to FSA as opposed to asking your questions here. If it's a common problem they'll be the ones to know and they'll likely be eager to set it right.

I can tell you that I've had no such problems with my Gossamer cranks in many years of ownership. If I were to speculate I would say that that is a defect and if the cranks aren't ancient (which they don't appear to be given your BB style) the manufacturer may well cover it.


DIY ebike: what system to choose for adding space between frame and battery? So, the project is to install this 5kg battery:

on this bike:

This is no joke. I'm serious.
Following up to this previous question, I'm going to use steel rivnuts (aluminium is really too light for the job), M6 if possible otherwise I'll fallback to the standard M5. I hope to have enough room to put at least 6 rivnuts, 4 being the absolute minimum I could accept.
Here are some dimensions of the rivnuts:

Now the point of this question. The frame has an hinge, thus I cannot install the battery right on the frame, there has to be a spacing of about 15mm between the frame and the battery. The battery goes from the fork to the seatpost, with just a few centimeters left, allowing to swap the battery out from its support.
So far, I could think of 3 solutions:
1) Use these steel hexagonal studs:

Pros: Visually, seems to be the "right piece for the job". Made of steel.
Cons: Probably not designed for such job, I'm afraid it could break between the thread and the nut part.
For the record, M5 model has 8mm thread length and M6 model has 10mm thread length.

2) Use long bolts and these "tall washers", between the rivnut collars and the battery support:

Pros: The most "regular" system one would think of.
Cons: Probably not the sturdiest system.

3) Use larger "tall washers", that would sit around the rivnuts collars, right on the frame, rather than on the rivnut collar.

Pros: Allows to use much larger, thus stronger, washers. For example, with M6 rivnuts I would use M12 washers, that have an external diameter of 20mm! That would help a lot for bearing the sideways force.
Cons: Maybe need to add a protection layer between the frame and the washers, so they don't leave a mark on the frame. Maybe a band of Gorilla Tape, with holes for the bolts.

So far, I'm bending towards solution 3. What are your thoughts on this?

I think a problem with option 3 is that the screw’s tightening torque is “pulling” the rivnut out of the frame (in addition to any force acting on the battery). With option 2 the frame only receives the actual forces acting on the battery.
Sideways stability should come from your mounts being several centimeters apart, not from using wide washers/spacers.
In all of this I’d make sure to use threadlocker and sufficient tightening torque (like >4Nm) to make sure nothing comes loose and starts weakening over time.
Oh, and one idea: Instead of rivnuts, why not drill through the whole frame and use very long bolts and a bracing plate (or wide washers) on the top and bottom? Or even just clamp plates around the frame without any drilling and mount the battery to the plates.


Chain skipping mid cassette after a clean I have cleaned my chain and gears with rubbing alcohol and towels. Afterwards, I applied some chain lube on the chain. Now, when under a lot of torque, the chain skips and slips mid-cassette. Low gears and high gears seem to be unaffected. There were no tweaks made to the front or rear derailleurs. Could the previous gunk have kept the chain centered on the gear? Is there any chance that the rear derailleur got tweaked in the cleaning process somehow? I did clean the two gears on it.

The bike is a 2007 Specialized Tarmac with about 4-5,000 miles on it.

It's possible that during cleaning a grain of sand, for example, has become stuck in the chain causing a stiff link which does not travel cleanly over the cogs. Cleaning chains and cogs often involves a significant amount of moving dirt around before extracting it.

A simple test for this is to move the chain through both hands bending every link. You'll find a stiff link very easily.

If that's the problem, clean the link until the stiffness goes, re-lube and you should have no further problems.


What is a good replacement for my MF-Z012 6 speed wind on cassette? I'm trying to find a good replacement for my MF-Z012 6 speed wind on cassette. Thing is, I've upgraded my bike with '93 Dura-Ace rear and front derailleurs. Trouble is they are 7-speed compatible. According to some digging I did, they might also work with 6-speed cassettes, but I'd like to play it safe and upgrade the cassette to 7 speed. Besides, not sure how great the old cassette's teeth are.

Also, I'd like to keep my original 6-speed Biopace crankset. Not sure if it's compatible with the Dura-Ace or with the 7speed cassette. I'm thinking it should be OK, since Dura-Ace also had a Biopace crankset version for the 7 and 8 speed groupset.

All advice is welcome.

1984 – Shimano introduced Dura-Ace 7400 series with Shimano Index System (SIS) the first successful indexed-shifting system in cycling history. It was a 6-speed (7 and 8-speed later) system with indexed shifters mounted on the down tube.

From http://cycling-passion.com/dura-ace-history/
Your front mech is given as a FD7400B, which doesn't really carry a defined number of "speeds" because 6/7/8 all used roughly the same chain width.  The B means it is a "band-on" fitting, not a F for "braze-on".  It is rated for a big/small gap of 15 teeth.
Assuming your rear mech is from the same age, it will be a RD7400 which is rated for 6 speed and 26 tooth max cog.  A RD7401 is a 6+7 mech and a RD7402 is an 8 speed mech.
The downside is that this generation of Dura Ace had a whacky cable pull ratio.  So its ONLY compatible with a Dura Ace shifter of the same number of gears.  You already have both.
The upshot of this is that you need a 6 speed freewheel, where the big cog is no bigger than a 26 tooth.
If you want more gears, you'll need a new wheel hub, cassette, rear mech, and right-hand shifter.   Practically that means a replacement wheel.  And your frame has to have enough width to take a wider wheel - the OLD on your 6 speed wheel might be 126mm and wider cassettes use more space.  All that is covered in other questions on this site.
From Sheldon's site

Myth: Dura-Ace cassettes have a different spacing, and are incompatible with other derailers/shifters.
Truth: No, all Shimano cassettes and freehubs with the same number of speeds use the same spacing, and index with any system configured for the same number of sprockets.

You also need to avoid a freewheel with a bigger cog than 26 tooth.  The top jockey wheel could impact the big cog and that's loud at best, and disastrous at worst.
There's some interesting info at https://www.sheldonbrown.com/dura-ace.html  but you have the DA shifters and mechs, so that's not super-relevant to you.

Your biopace chainring won't care what you do at the backend.  Front shifting might get a bit twitchy if you put a thin 11 speed chain through a front mech intended for 6 speed, but it just needs to be pushed over a bit more before the chain gets shoved.  Easy.


Why is the Shimano R3030 FD not compatible with the 3503 FC? I have an older version of the Triban 520 with the Shimano Sora 3503 groupset (3x9 speed). I neglected it for two weeks over winter and the salt has done some damage. The spring in the front derailleur no longer returns the cage. I am looking at replacing the front mech. It seems much easier to find a R3030 front derailleur rather than the older 3503 front derailleur.

From the Shimano compatibility documentation I can see that the the 3503 shifters are compatible with the R3030, 3503 and R353 front derailleur. Though, it seems that the R3030 front derailleur is not compatible with 3503 crankset. Can anyone explain why this is the case and suggest a suitable replacement?

This is from a long time ago, but for the sake of others, I believe it's because of the cage size, I was trying to do the opposite with an r3030 crank and 3503, and I was not able to get it to shift smoothly until I paired the r3030 crank with r3030 front derailleur.


Cold hands due to cold/wind What is a good way to not have my hands/fingers freeze on bike rides in the cold/wind? I have a pair of gloves, but it doesn't fix the issue. Is there a better way than just to get a really thick pair of gloves that will be unwieldy.

The most important thing is to make sure your core temperature is high enough.  As your body begins to chill, it pulls blood away from the extremities, to maintain its core temp.  Often times cyclists will think "my core temperature feels fine, but my hands are cold" so they think they need warmer gloves, when in reality they need another jacket/vest/jersey/base layer.

Also, remember body heat is generated in your torso, and has to be piped to your hands.  If, for example, you were riding with bare arms, and giant oven-mitt gloves, your hands would still get cold, because the blood would have lost too much of its heat before ever reaching your hands.  Again, long-sleeved jacket/jerseys, base layers, and arm warmers can all help significantly with keeping hands warm.

Good gloves are important to keeping your hands warm, but they're just one part of the chain, and if any of the pieces are missing, not even the thickest, warmest gloves in the world will stop your hands from getting cold.


How can I update the brake system on this vintage Universal La Riviera ladies bike? I would be really grateful for any advise on how to go about updating the brake system on this vintage Universal La Riviera ladies bike.

The brakes don't work properly so I can't safely ride it. The front brakes are very stiff and the back breaks have completely seized.

I tried to oil it but I think the rust damage is too extensive and it's probably too old to salvage. I'd like to install a new brake set but I'm not sure what kind to buy. Do I need the exact same model or can I change to any brake system? If I can use another brake system could you please let me know your recommendation and why it's better?

Here are some photos:

The back brake lever has seized with rust.

Front brakes function but very poorly.

Back brakes.

Back brakes.

The bike.

A friend donated this bike to me. From what I read of the company, the bike is probably from the 1980s. It's very rusty but the frame is sound, the wheels look fine and there's no problem with the steering. I recently put on a new chain and now pedaling is smooth. There's a problem with changing gears but everything's fine if I don't try to change gears. I only use it to go to my local shops a few times a month so I'm happy as long as it's functional and safe. :)

Many thanks in advance for your time.

The brake pads are almost certainly hardened and need replacing, and the cables probably rusted and stiff, so also need replacing. Both these items are considered consumable and relatively cheap.

Before going out and buying new ones, I would remove the cable and check the levers are free. Also check the brake calipers are opening and closing freely and spring back when released.  A spray of WD-40 or penetrating oil may be needed if really stiff, but once freed up a squirt of a light oil or chain lube will provide lubrication.  If you can get these moving then install the new, high quality pads and cables and they should work better than new.

Replacement brake levers and calipers are easy to find if you're not after exact, era-accurate replacements.  Your local bike co-op or recycle center is likely to have brakes or a donor bike.

Installing cables is best done with a proper cable-cutting tool. It's possible to cut cables with other tools (such as a Dremel), but it's probably better to hand it over to the LBS if you don't want to purchase a tool and cannot get access to one.

As suggested by @Daniel, the bike is not worth a lot, and you could very quickly end up spending more on the bike than it is worth. Before spending too much time and money I suggest looking very closely at the tires, as if original these are likely perished and in need of replacement.


Best practices for commuting with rack & panniers I've been starting to commute by bike more (about 6 miles each way) and decided to upgrade from my cheap, old mountain bike to something more suitable. I just bought a used 2009 Kona Jake off Craigslist. Pretty excited about the bike -- it came with fenders, rear rack and two panniers.

Previously I've just carried everything in a messenger bag or backpack when riding. Panniers are new to me. What are some tips you have for packing and riding with panniers? I'll be carrying a laptop part of the time and beyond that a book or two, a lunch, maybe some clothes and other miscellaneous bits.

For example, I'm wondering:

If I don't have much on a given day, should I just use one pannier or try to distribute between two? In general, how important is it to keep them balanced?
Should I be concerned about heel spacing or getting on/off the bike? (In my initial short ride, it wasn't an issue)
When I have more weight, how much will it change the stopping distance and the bike's balance?

Unfortunately, the bike's in to get a tune-up so I can't recall the make of the panniers. Beyond the rack hooks, there's also a strap that runs from the middle, has a hook on the end and some velcro that attaches to the top of the bag. I can't figure out what they're for.

** Edit **

Here's a photo of my new (used) panniers. They're by D2R.

In general panniers are more comfortable and efficient than carrying weight on your body. There are some things to be aware of, however.

Safety. Every time you set off, make absolutely sure that all the pannier straps are done up. Apart from things falling out, the last thing you want is a loose strap getting caught in the spokes. This can wreak a wheel, and a rider!

Regarding stopping distance, I don't think it makes much difference as the weight increases the friction between wheel and road. However, the extra weight does contribute something to heating the brake pads and rims/discs, but it's probably only an issue on long steep descents which are unusual on a commute.

Panniers getting in your way. Yes, aim to keep your heel clear of the bags. This can be different when the bags are fully-laden as they tend to bulge further than expected. Worst-case you can pedal with your toes pointed down to avoid heel-strike, but this isn't comfortable for long. If you swing your leg over to get on and off then definitely take a bit of extra care to avoid pratfalls. Also be aware the rear of the bike is slightly wider.

Left-right loading. Ideally it's nice to have them balanced, but unless there's more than 5kg difference between the sides, I'd say it's not really noticeable. So if all you're carrying is clothing and spare shoes, then it should be fine to take just one bag. However, if it's a stack of books consider two half-filled bags.

Vibration and bumps. In my wife's experience, laptops seem to suffer from vibration in panniers more than rucksacks/messenger bags. Hers acquired a serious soundcard issue after being bounced in a pannier back down a slightly bumpy road. I'm not talking about crashing or dropping the bag, just riding the normal bumps in British roads. Your road surface may vary. Putting sensitive kit on your body is less comfortable for you, but more protective for the kit.

Consider waterproofing. If the contents are sensitive to moisture (like the laptop), then you may want to double-bag unless you're really confident in the pannier's waterproofing.

Tire pressure. Adding weight to your bike means you'll need a slightly increased tire pressure to prevent pinch-flats, particularly for the wheel over which the weight is situated. There's another question with some more information on calculating the best tire pressure, but ideally it should be done per-wheel and adding panniers to the rear will make this more important.

The strap that runs from the middle with the hook on the end may be to wrap around the lower part of the rack (and possibly back up to the pannier). The aim may be to stop the pannier from swinging out away from the bike or from jumping off when you go over a bump, but in my experience if the strap is made of elastic it doesn't prevent this. The best design to stop the panniers hopping off is a clip which fully-encloses the top horizontal bar of the rack, as is found on Ortlieb and many modern panniers. If you want more detailed advice, post some pictures when you get the panniers back.


Disc Brakes: Resurface your Pads? Is resurfacing the brake pads in disc brakes (hydraulic or mechanical) necessary?  If so, what would you use to do this - medium sandpaper?

I spoke to one mechanic while shopping for a bike, who suggested resurfacing on a monthly basis...

You've met a mechanic that either wants you to buy more brake pads from his/her shop or doesn't know what he/she is doing. There's really no good reason to resurface your disc brake pads, let alone on a monthly basis. All that's doing is decreasing the life of your pads and temporarily decreasing your braking power until your pads bed back into the rotors.
I think that the reason some mechanics feel the need to resurface disc brake pads is a carryover from the need to resurface rim brakes, which do need to be resurfaced in some instances.


How to route shifter cables along frame to a Rohloff external gear mech? I am currently converting my Rohloff's gear mech from the internal to external version, and I’d like to route the shifter cables along the downtube and chainstay. However, I’m not sure how to route the cables from the shifter on the right side of the handlebars to the gear mech on the left side of the rear wheel. What attachments might I need for this beyond any brazes on my Surly LHT (non-disc) frame? Does anyone have a few high-definition photos they could share of their working and time-tested setup?

As you have a steel frame, you will get the best result if you have a competent framebuilder add the appropriate brazeons. There are two sorts of brazeons that one could use:

Cable tie guides, where the cable housing is fixed in a groove with a small cable tie (looks much better than a big cable tie around the entire tube!)
various shapes of short tubes or rings, where the cable housing is fed through

Have a look at Ceeway for what is available (or talk to your framebuilder).

For a visually pleasing end result, the frame will need a new paint job after adding brazeons.


Does tire pressure affect rolling resistance on pavement? It's a no brainer, right? Yet a comment links to a blog post claiming to have scientifically proven there is no significant effect. It looks solid but is not a paper in a peer-reviewed journal.
What is the current understanding of rolling resistance of a slick tire on pavement?

This study:  William M. Bertucci, Simon Rogier & Raoul F. Reiser II (2013) Evaluation of aerodynamic and rolling resistances in mountain-bike field conditions, Journal of Sports Sciences, 31:14, 1606-1613, DOI: 10.1080/02640414.2013.792945
is very far from comprehensive, but it reports rolling resistances for two pressures (2 and 4 bar - 200 and 400 kPa) for wider tyres. Of them, Vittoria Radonneur could be considered reasonably slick. They report slightly higher speed and slightly lower rolling resistance, but with a large uncertainty, with 2 bar on 5.9% road slope. The uncertainty is larger than the difference 12.6 ± 3.4 N at 2 bar vs. 13.5 ± 2.2 N at 4 bar. Be aware that this is the force, not the power required to overcome it at the given speed! The study did not really concentrate on the effect of inflation pressure and they conclude that the difference is not statistically significant. Interestingly, the idealized measurement in the link I already gave say "When using these tires, you should monitor air pressures very closely. Don't let these drop under 60 psi EVER.". (60 PSI is 4.1 bar)
Another study used a smooth treadmill:  Yves Henchoz, Giacomo Crivelli, Fabio Borrani & Grégoire P. Millet (2010) A new method to measure rolling resistance in treadmill cycling, Journal of Sports Sciences, 28:10, 1043-1046, DOI: 10.1080/02640414.2010.498483
It found that for two tyres (23 and 28 mm) the rolling resistance decreased uniformly with the inflation pressure. For the third tyre (22 mm) the lowest inflation pressure was achieved at 6 bar (600 kPa) and then it rose slightly. I stress again that this was not on the tarmac but on a smooth treadmill.
Very comprehensive measurements of various tyres with several different inflation pressures are regularly published by https://www.bicyclerollingresistance.com . They test a single wheel in a dedicated machine on a rather idealized surface. The rolling resistance mostly uniformly decreases with the inflation pressure in these conditions although the curve is often quite flat at higher pressures.

An example of the dependence of the rolling resistance (as a power required) to the inflation pressure on the idealized test bed of https://www.bicyclerollingresistance.com for four road tyres.
However, a study by SILCA indirectly mentioned in the comment by R. Chung considers real asphalt concrete surfaces and found that the suspension losses/transmitted losses/impedance are quite substantial at higher pressures and cause turning of the resistance curve upwards. It isargued that a tyre that is "too hard" suffers from high resistance when overcoming and jumping over the small bumps that create the tarmac surface.
A schematic  explanation by SILCA, more in the study:


My bike suspension is very stiff how can I make it looser My ozone 500 ultra shock mountain bike suspension is very stiff how can I make it looser I've tried oil ,wd-40 ,and other things please help me my bike is so bouncy

This is a bso.

The suspension is there just for looks, not for actually doing anything useful, and you don't really have adjustment on it, or the ability to lock it out. That is, you can't do anything. In your case, you want to make the suspension stiffer not looser to reduce the bouncy-ness. That is, if the suspension was fixed, it wouldn't bounce so much.

In general, suspension costs money to do well. You're looking at ~400-500 USD for bicycles with basic servicable suspension forks, and ~1500+ USD for bikes with acceptable full supsension.

Decent suspension forks will have some adjustability, and possibly the ability to lock out (i.e. act like a rigid fork). Rear suspension systems of the coil type need a different coil (with a larger spring constant for more rigidity) to adjust significantly. Other types have other adjustments.

Note that for riding on the road, you don't really need suspension (for comfort, larger tires are often a better choice). And the suspension on your BSO won't really cope with any non-trivial rough stuff off road (note that these bikes are sold typically with stickers saying not to use them off road).


What options to transport both heavy backpack and gym bag via bicycle I ride my bicycle to school everyday with a backpack filled with books, papers, and a laptop . Some days I also carry a second backpack with gym clothes and shoes. There isn't room to fit the gym clothes in the backpack, nor would I want to even if they could fit (sweaty clothes and papers don't mix). But carrying two bags is awkward too, the second bag can't be easily carried comfortably alongside the first, it gets in the way of pedaling etc.

I had hoped to find a product out there where you can get an backpack which can attach a secondary bag, similar to how hikers attach sleeping rolls to the top of their backpacks. While some backpacks come with bungee cords on the front, it's not clear that this can be used to attach a bag.

This answer to a similar question shows a hiking backpack which includes a smaller detachable daypack. This is far too large for a daily commute though.

Other than that, what I was imagining doesn't appear to exist.

What solution will allow you to best carry a heavy backpack and a light gym back comfortably and portably, especially for when cycling? How would you combine your gym bag with your backpack?

Get a rear rack for your bike and strap the gym bag to it. A low cost and much safer approach.


What are my options for replacing a Shimano Hollowtech II BB? I have had a 'Deore' equipped mountain bike for 3-4 months now. However, there is grinding noise from the area of the cranks and I suspect the bottom bracket.

On a local MTB forum I heard that Deore BB's last exactly that long. So I am worried about replacing the part with an exact duplicate (for fear of short service life).

Do more expensive Shimano groupsets use the exact same BB or is it different for each? Do they last longer? Is it normal for a Deore BB to fail after such a short time?

There are a number of options for replacing a Hollowtech II BB (whilst still retaining the Shimano cranks). The Deore bb is a cheap bb, higher Shimano levels should last better. Anecdotally I've heard premium Bb's last years while it's not unusual to use a Shimano BB a season.

The options are:

Shimano - Shimano has a number of different levels. BB51 deore level, BB70 SLX/XT and BB93 XTR
Other similar brands - Raceface X-type is compatible
Premium brands - Hope, Chris King and others
Hacks - replacing and upgrading the bearings while retaining the Shimano cups.

If you kill many bottom bearings it's good to understand why and address this. Water retention in the shell is a big issue if you ride in wet areas as is washing the grease out with a pressure washer. There are Bb's that have water drains built into the cups for drainage or you can drill a hole in your Bb shell if this is a real issue for you. Sealed bearings offer better water protection.

End of the day it's really a value choice, if you go through a lot of Bbs you should consider a premium one.


Identifying extra triggers in a speedometer The HRM, GPS, and cadence in my cyclocomputer give perfectly good readings, but the speedometer (and hence the odometer) readings are obviously incorrect.
Because the speed and distance readings seem to be just about twice what they should be, I'm guessing that something other than the dedicated magnet is triggering the extra events.

Might the Presta valve be magnetized and provide that extraneous trigger? Since the cadence and wheel receiver are in the same piece, there is not a lot of flexibility in moving the dual-receiver far away from the valve.
Have you been there? What are some ideas to debug this issue?

The problem went away after a firmware update. The most likely interpretation is that the reed switch is generating two pulses for each pass of the magnet, but now each double-pulse is interpreted in software as a single pulse. It's not ideal (hardware with one defect has a higher chance of also having other issues), but it's accurate.


Bike measurements vs my measurements I would like to buy a used Rose Pro DX Cross bike (model 2014 or 2015) and its size is listed as being ST-56 cm and TT - 54 cm. I'm 178 cm in height and my inseam length is 79 cm. Do you think it's suitable for me? I don't want the top tube to hurt my groin when I dismount it to wait at traffic lights or anything like that. Thanks a million!

Best wishes,
Florin

The only real way to determine if a bike fits you is to sit on it and ideally ride it.

In addition to making sure the stand-over clearance and set height range are OK, you need to determine if the position of the handlebars relative to the seat works for you. Lower, forward bars means a more aggressive riding position, higher rearward bars allows a more relaxed riding position.


Are bicycle registration websites any use for recovering stolen bikes? Ther are quite a few bicycle registration websites aimed to help you recover your bike if it is stolen, such as Bike Shepherd, Bike Register and MyBikeNumber. I'm curious if these sites are of any use.

What are the strengths and weaknesses of registering on these sites?
Is there any data available on their efficacy?

The two questions that I think matter are:

which sites do your local bikes shops check all the bikes that come in against?
which sites do your local police check bikes they receive against?

In my experience bike shops very rarely check bikes at all, largely because so few are registered (and a relatively low proportion of serviced bikes are stolen). When we have checked it's been because of something like filed-off serial numbers or a DIY repaint job, and we've not ever had any joy doing so. Even ringing the police in one case didn help - the bike hadn't been reported as stolen.

As far as the police go, I've been told by one officer that at least in Australia the best you can hope for is them typing the serial number(s) into google.

You're better off keeping a record of the serial number and reporting your bike stolen with those details, because the police do actually check serial numbers (it's built into the computer systems).

One thing that also helps is carving your ID number (national ID, driver's licence, whatever is common in your country) into the frame or something obvious like the outside face of the cranks. That makes it irritating to remove and again, easy for the police to identify but not easy for anyone else. If you have access to an engraving tool itś not hard to do this (practice on something first!), but of course it also makes your bike hard to sell.


Folding bike vs mountain bike I'm thinking of giving up my heavy Trek mountain bike for a folding bike. Anyone made the move to folding bike regretted it? Why?

I'll be using it around town, shopping, etc. We have a small apartment without storage.

My stable contains two folding bikes, and I love them both. I use them for different purposes. If this is going to be your only bike and you want to use that bike for cargo (with racks, etc), I recommend against using a folding bike unless it's one with larger wheels.

Disadvantages of folders:

For offroad riding, nothing beats a standard rigid-frame mountain bike. If you forsee a decent amount of offroad riding, I strongly recommend against getting any folding bike.
Coasting on a folding bike isn't quite as easy, due to the diminished momentum of the smaller wheels. This is a very minor point, though.
Getting parts for a folding bike can sometimes be a little more difficult. A little planning can alleviate this, as can keeping spare tubes, spokes, etc around the house.
Mounting panniers on a folder's rear rack tends to result in heelstrike, unless you have a folder with a very long wheelbase that's meant for touring. If you want to use this bike for shopping, that's a point against folders.
Folding bikes are more expensive, and can be heavier, then their non-folding counterparts.
Folders usually have a weight limit. The wheels are usually smaller and therefore sturdier than larger wheels, but the frame is a limiting factor. For example, the Dahon Curve has a rider limit of 100kg/220lbs. (When I bought mine, that was an across-the-board limitation, but they may have improved that.) So if you're a big guy, look into this.

Advantages of folders:

Storage is easier, obviously. A plus in small apartments. It's also simpler to put the bike in a car trunk or back seat, or take it on public transportation.
You can accelerate crazy fast on a folding bike, for the same reason you have to put a little more effort into coasting - the wheels are smaller and therefore lighter.
Small wheels are fun! Folding bikes can be more nimble than bikes with full-sized wheels.

I love folding bikes, but unless you have no other options, a small-wheeled folding bike wouldn't be a good fit for your purposes. A folding bike with 26" or even 20" wheels, however, might work very well if you can fit it with a rear rack. Try one out in a store and see how it feels and if you can carry cargo easily.


Sun protective clothing interfering with bike mirror I have had a "third eye" type bike mirror on my helmet for years.  However, recently I have learned of some genetic predisposition to certain types of skin cancer which affect the skin on the face/head and have become more cautious about how I approach the sun.  As a result, I have taken to wearing a protective "sun drape" but I wound up having to modify it because even with my helmet and the drape, part of my face is still exposed to the sun at times.
Anyway, the consequence of this is that when my face is fully protected from the sun the protective drape sticks out a bit and I can no longer see the third-eye mirror.  I'm not okay with using sunscreen instead, so I have been experimenting with other ways of mounting the mirror, but have not been able to find any that work - for instance, mounting the mirror on the side of the helmet away from the sun results in my not being able to see the important part of the road due to my back being in the way, and all the mirrors I have tried that attach to the bike I can't see when I'm hunched over the bike for speed and in most need of a quick check of the traffic behind me.
One idea I had was perhaps a strip mirror under the top of my helmet's visor might work, but I haven't seen anything like that.

  from
https://www.coolibar.com/unisex-trailhead-hat-drape-upf-50.html

This is complicated.  The farther from the eye a mirror is, the larger it must be to provide an adequate field of view.  This is one of the (several) reasons that bar-mounted mirrors are often unsatisfactory.

Assuming you stick with helmet-mounted, you do want to get the largest mirror you can find, and one with a relatively long arm, so you can get it as far out to the left as possible.  But I find that even without any helmet covering, this doesn't quite allow me to see around the helmet.

What I do is aim the mirror so that, when I'm looking straight ahead, the mirror gives me a view of the left shoulder of the road.  Then, when I want to observe traffic behind me, I turn my head slightly to the left.  This give me a view behind, and the turning of the head adds sufficient leftward extension to the mirror to allow me to clearly see past the helmet.


Is there a way to fill your tires with nitrogen? I know this is a rather controversial issue. I was skeptical as well before doing this on my car, and I have not refilled my car tires for several months. Before that I needed to adjust the pressure every couple of months at least.

Now I think it is a good idea to try this for our bikes. Especially since, when I see I need to fill up my bike tires, I get too lazy and give up the ride altogether.

Is there a way to do this at home?

EDIT:
I thought I'd update the question for people who come and read later:

Thanks for all the comments, I drive a lot (30kmiles/year) and I saw (to my surprise) a significant difference with nitrogen.

I understand the reasoning with losing oxygen over time and increasing the N2 concentration but in practice that does not happen fast enough.

I think I'll look into Helium/Argon and I'll update you if I managed to do something interesting.

And I live in a small place I don't like to have a large pump but that is exactly why pumping is such a chore for me,

I am going to be presumptuous enough to ask what I believe is the question behind the OPs question, then answer that...

The problem is that you have to inflate the tires more often than you like. The question then is what can I do to ensure my tires remain inflated for as long as possible.

The answers
Tubes - these keep the air molecules in. Thicker is better, as is better material. Dump the super thin light weight race tubes and get the thickest one you can find, I would even suggest giving cheap chain store tubes ago.

Tires - Bigger tires can carry the same weight at lower pressures. Put in bigger tires and run at lower pressure. This has two effects - lower pressure leaks molecules slower, and more volume means those leaked molecules are noticed less.

Exotics
Look at the no-tubes and 'no puncture' slime solutions - these seal the holes the air molecules are escaping from.

As previously suggested - invest in a decent pump. If you don't have room or desire for a floor pump by the door, get a pump that uses CO canisters (and wear the cost of canisters). If it is still a pain to pump up your tires - discard the plastic valve caps, and get rims/tubes with presta valves - it will take less than 30 seconds to top up two tires.

You might have guessed all these solutions add weight and move away from the best of the best in terms of performance- well, that is expected, nothing is free and super light weight fast racing tires leak air, after all, as long as they stay inflated for the stage - up to 8 Hours, that's all that is needed and any longer is excess weight.


My tyre has hollow knobs, is it normal/desirable/essential for maker to disclose? I noticed my back tyre has hollow knobs and I can't remember ever seeing this before. Some of the knobs have turned out to be hollow inside. I know YGWYPF, my questions are:

Is it normal? I got no meaningful results with google.
Is it desirable on a budget (even cheapskate really) tyre? It wouldn't
surprise me on a £££ model, but in this case my guess would be that
it would not meet the balance between extra cost of manufacturing
complexities vs the savings on raw materials.
Shouldn't the label say the knobs are hollow? My loose thoughts
would be that this has a bearing on a user's ability to assess
things like performance and remaining life? Even if it's the
subconscious visual assessment of these? I bought this in the UK but it's a global brand (and so is probably the model).

I'm aware many on here would argue this tyre is way overdue for replacement, this is not what the question is.

Edit: Clarification in response to some early comments.

I can't tell for sure if this is a manufacturing defect, it might be, but I think this is part of my question really.
The holes do not seem to go through the casing to the tube inside. The best way I can describe it is that it seems like they are hollow blocks/knobs glued onto a slick tyre. It also seems that the hollow space inside the hole is bigger that the opening that has been created.
I estimate I've ridden 100 to 1000 km on this tyre, 95% tarmac (from dry to heavy rain), 5% well compacted gravel path, very little harsh braking. Estimates are very rough because I don't use any tracking and my cycling comes in irregular spells of commuting.
They do indeed seem irregular. To me, this could equally indicate "unintended error in manufacturing" or "intended by design but poorly executed". The photos are a decent indication of the number and spread/distribution around the whole tyre. I'm fairly sure I didn't ride over enough broken glass (or similar) for that to be the main cause.

I don't think the tread blocks are 'hollow' exactly.

Tires are made up of layers of different formulas of rubber. I think you have worn though the outer layer and a little chip of rubber has flaked out of the center of some of the the blocks. Now you can see that the next layer down has de-laminated from the outer a little, so it looks like there is a void there.

If the blocks are hollow, the void is only right at the bottom of the block, and would only be exposed if the tire is very well worn, as yours is.


Which Mountain Style Shifter for Early 90's Shimano 105? Converting early '90's Trek 1400 from traditional road bars to a flat/straight mtn bar. Converted V-brakes over to use Deore brake levers. Works well. Need to get the shifters up to the bars, replacing the originals on the down tube.  Which shift control/assembly do need ?  (original Shimano 105 components).

For the rear, any Shimano shifter (for the right number of speeds) will work - the cable for the rear is the same between mountain and road. On the other hand, the front derailleurs have different cable pulls, and you need the flat bar road shifter (one of these). You can get the Sora set for 8 speed assuming your bike has an 8 speed cluster in the back (Shimano ST-R221 for the front , Shimano SL-R440-8 for the back). They are pricey though compared to their mountain brethren, and you only need the front one from that pair - the rear can be an 8 speed Alivio or something, but it wont look as nice (but function fine).

Some alternatives for the front: depending on if you swap in a closer spaced crankset, you may be able to get a mountain FD to shift it and get a mountain set [depending on how the FD is mounted]. Or more simply, buy a friction shifter for the front and an index shifter for the back. A friction shifter is like 5 bucks for a thumb mounted one.

Also, note that the riding position does change when you switch from drops to flats, so I'm assuming you've worked out those details already.


Identifying small, moped-like bike I found a very cool and bizarre-looking bike in Berlin (in Germany) and was very confused about what it in fact "is"; Has anyone got an idea? — To me, it almost looks like some sort of cannibalized bike/moped/mini-motorbike hybrid:

The owner was an older guy who told me that it's "custom" but he had bought it the way it is except for the front case and Winnie-the-Pooh squeaker, which he'd added himself.

Looks like 70s Schauff Elite. Compare it with bike here, the frame has very distinct shapes. A similar bike is also listed at the official (correct me if I'm wrong) Schauff website, the picture under number 28.


How do I thread rear derailleur cable through this adjuster? this is a Lemond Zurich from around 1999 that I'm converting to 10 speed in rear. I can't get the cable to thread past this metal part that seems to be a fine adjustment for rear derailleur. I can't pull it apart. There is a spring mechanism between the part attached to bike frame and the rotating adjustment. Any experience with this? Ideas?
Thanks,
Bob

They don't pull apart; the idea is that you're getting the couple mm of adjustment range you actually need, and the upside is it's an attempt at the easiest possible design to adjust on the fly while riding. If there's something physically blocking the hole for the cable, you could presumably clear it by poking a pin or needle through. Make sure the cable isn't actually getting stuck at the end of the housing though, either by the ferrule or by the end not being prepped properly.


What non-metric fastener heads are left on a standard bicycle? I believe that we've for the most part made the transition to metric on contemporary bicycles -- at least for the tools we use to repair them, am I right?

For example, while many screw threads are still imperial (or whitworth or some bizarre French/Italian/British concoction), the actual fastener heads or shanks are metric. For example, pedals are  9/16" x 20 tpi  but we've standardized on 15 mm for the pedal wrench (or a metric allen). Solid axles might be 9mm x 26 tpi but again we've standardize on 15mm for the nut.

Are there any parts of non-BSO bikes coming off the line where we might still expect to still need a non-metric tool to take a component off of?

Very rare, but I believe some pedals still require a 9/16" spanner to remove them. Not to be confused with the 9/16" axle like you have mentioned. Park Tool still make a pedal spanner with both a 15mm and 9/16" opening. Considering 9/16" of an inch is 14.3mm and the chances you'll actually have to remove one are fairly slim, I'd be happy with just a standard 15mm pedal spanner.

Beyond this I can't think of anything else. Perhaps wheel nuts on very cheap kids character bikes? Some of those seem to come with whatever the factory had going spare at the time of assembly!


Do certain makes/models/types of bikes get stolen more than others? I was reading this article on the most commonly stolen cars, and having my bike stolen recently, I got to thinking: do certain makes/models/types of bikes get stolen more than others? My bike was a 15 year-old GT Aggressor 2.0 (Mountain bike) and it was stolen out of my back yard. I just have a hard time thinking that someone was seeking out that year/model.

It would seem that most bike thefts are crimes of opportunity, opposed to targeted attacks, but I don't see any data to back that up. Also, it seems like for cars, the cars that are stolen the most, just so happen to be the same cars most commonly driven. I assume the same would go for bicycles?

Any bike thieves want to chime in?

I'm a lifelong cyclist, including big cities like SF, Oakland, Baltimore, DC, Atlanta, etc...   And I've worked in a few bike shops so I've heard several stories.

Basically, there are 2 kinds of bike thefts:

Crimes of opportunity. Meaning, if a thief thinks they can sell it for $20 or more and they think they can get away with it.  These folks will steal any "decent looking" bike. These thefts are atributed to drug addicts.  But, I've heard of all kinds of people doing this.  Some do it for the thrill.
"Professional" bike thieves.  The kind that patrol cities and universities looking for bikes that they can flip on craigslist or ebay for good money.  They sometimes patrol in vans stealing a dozen in one night using professional tools.  They usually steal in one city and sell via craigslist in another.  These guys know the difference between cheap bikes and nice bikes.  They go for the latter exclusively.

Also:

No bike is 100% safe, even in your garage, house or apartment.
No lock is 100% safe.  They just buy time.  A cheap lock is worth about 5 seconds.  An expensive lock is worth about 10-15 minutes.  If the thief has the time and won't be interrupted, they may go for it.


Rattling of a Shimano Nexave roller brake In a suspended fork I use a Shimano Nexave BR-IM75-F roller brake and the cooling disc of the brake is not tighly fixed on the hub and it was like that since I got the roller-brake installed. I'm not sure whether this is "by design" or a fault. Opening the brrake side of the hub didn'r reveal nay way to make the fit tigher.

Anyway, It works fine for stoppping, but when I go over rough terrain the disc seems to rattles a lot, which creates quite a bit of noise. - Not nice!

Any idea what I can do?

Here is a picture of the Brake (I hope it helps understanding the situation!):

I have these fitted to my Carrera Subway 8.

They seem to work well, but yes they rattle quite a bit when going over rough ground.  The cooling fin becomes tight when the brakes are applied so must be a direct connection to one of the friction faces.

I might have a go a dabbing a bit of silicone at three points around the interface of the cooling fin to see if it subdues the rattling :-)


Any issues with wearing leg warmers over tights? I want to add a layer over my bike tights for warmth. Leg or knee warmers seem like a nice versatile option. I am just wondering if there is any issue with wearing these over tights as opposed to over bare skin with shorts.

I've worn my knee warmers under my tights, it worked well to keep me warm and they stayed in place well.  However, the tights were the kind that went over top of my standard bib shorts, not the kind of tights with integrated chamois.

If you want to try and wear them over your tights, you might need to get a larger size kneee warmer, depending on the thickness of our tights. You might also have trouble with them staying put, since they tend to be held up partially by the bottom of your cycling shorts.

Personally, If it's colder than my comfort zone with just tights, I'll usually wear a pair of stretchy synthetic knickers on warmer days (like chrome telegraph knickers) or some breathable shell pants (north face resolve) on colder days over top of my tights to help kill the wind and retain more heat.


Rear V-brake pivots (cantilever studs) asymmetrical on Specialized Hardrock XC 2004 - how to fix? This is a bit weird question. I bought a Specialized Hardrock XC used bike cheaply on e-bay. It had no front brake and the rear v-brake had different arms and was very dodgy. I thought I would able to fix what needs to be fixed - essentially to replace brakes shifters and cables. It would be fine, but for the unexpected.

( Studs that can be e-bay ordered from Taiwan)

The frame is good apart from the left rear V-brake stud (the cylinder piece on which brake is put on) - also called brake pivot and cantilever stud. It is protruding from frame by about 2 mm more than the right, also has a thicker ring at its base - so looks like as if it had not been screwed in all the way. If you look at the photo it looks like the disc shaped wider part has remained above the frame. Moreover - the part which the brake fits on that should be round (it is like a cylinder in the middle with flat sides used to screw studs into the corresponding frame threads) apparently has become oval - the left side brake does not go down all the way to the frame as the right side brake does and the fixator pin inserts into its hole by about 1 mm max. This is the problem I was trying to solve - if the brake would fit, I would not bother with the thing that one sud protrudes by 2 mm more.

The trouble I have is this - how do I replace the stud or what should I do. I have heard that one way would be to try to screw it more in - unlikely as the previous owner would have done it. The other way - to try to screw it out. After I could not fir the brake I tried to use mole grip wrench and understood it would be very difficult - tried just twice and stopped not to break the thing further. Another option maybe would be to file down the existing stud so that the brake fits on safely.

And how do I even know that the thread in studs from Taiwan would even fit the thread, should I be able to remove the stud? So I am worried to mess up the frame.

The brake I am trying to put on is Shimano Deore M590.

What do more experienced people think - how to sort this out? I am only a technically inclined noob in bicycling and would be very grateful for advice.

Thanks for the help. Finally what I needed to do was to screw the stud further in. The previous owner apparently had screwed it 2 mm out because in their wisdom they put a different V brake lever on the left hand side - which fitted better if the stud was protruding. Actually a guy from the local bike workshop did the screwing part for me, since I was afraid that I might damage the frame if I do it incorrectly.

Front brake studs were totally absent from the fork, so I got 10 mm diameter studs - similar to ones in the picture above from e-bay for 8 £. Happily bicycling now. :) - there is something very satisfying about getting a used bike with a good frame and fixing it up, learning as you go.


Weird whistling from the rear derailleur Shimano Deore xt, 10sp. The noise happens only when I change gears for the short period of time when the chain is moving from one sprocket to another. While pedaling on one gear it works well and silent. The chain is not new, but is not worn out, no skipping or jumping etc.

What can be a reason for this?

I've come across this before, but never on my own bike. The real cause was never identified, but I believe stripping, cleaning, and oiling the cage and jockey wheels was the fix. That leads me to suspect that a little sideways pressure during the shift caused something, like a bit of grit, to rub.


Replacing the Trek Lime I purchased a Trek Lime for my mother a few years ago.  Unfortunately, it has now been stolen and I need to replace it.  She has terrible arthritis so any bike that would require her hands to do more than hold on would be out of the question.  I've considered buying a cruiser and having an automatic transmission such as the nexus hub installed, but I'm just not familiar enough with automatic transmissions to be sure this is even possible. To complicate matters, I'm working out of the country for the next year and a half so I have to rely on others.  Does anyone have any suggestions?  BTW--I'm not willing to spend thousands of dollars on it.

If she liked the Lime, why not look at the second hand market. Get one and have it serviced by a good bike shop and off she goes...

Edit : Quick 1 minute search and I found This - why go second hand.....


What are the missing accessories for you cyclists? I am a technology guy and I would like to ask you cyclists, what are the missing accessories with your bike that you want us to do for you? In a project at school, I am asked to use the following sensors: gyroscope, accelerometer, microphone, barometer, magnetometer, compass or the various devices: cameras, geo-location, RFID, wireless transmission, ultra low power devices to make a useful accessory for you guys bikers. Can you guys tell us what are the obligatory accessories you need for your bikes?

H. P. - welcome to bikes.se and thanks for asking.

One feature I have not seen on bike computers or iphone apps is a simple tool that tells you how much money you have saved through cycling.

To drive a mile takes a certain amount of petrol/diesel and that depends on many factors. These factors can be approximated in a multitude of ways, so you can start off with a simple miles to the gallon factor then extend the model to take into account the start/stops, the speed, the weather (A.C. in summer), car engine size and so on. Some algorithm optimisations will not be that big a deal, others will be important to accuracy.

The car data is also important. As well as efficiency there is also the depreciation, insurance and other costs. You could have ballpark figures for 'large saloon', 'small hatch', 'fullsize SUV' and so on. Also there is the difference in saving depending on whether or not the car is given up.

Fuel prices change by the day and by region. Applying accurate prices to the data is another factor that can be approximated or accurately modelled. For instance, if we were to have another war or gulf hurricane then prices could go off the chart, so you can either model 'today's prices' or make the data tied into the price by date. Clearly this data needs to come from somewhere, either it is manually keyed in or else it gets it 'from the cloud' somehow.

Ideally the app just needs to know what car you drive or what car you sold. After that it should be able to work out the rest.

To what ends?

You could have this data used by employers wishing to remunerate employees for cycling to work, you could also have parents that 'run a taxi service' make pocket money dependent on whether the kids cycle to school or not.

As a spin off you could also measure Kg of CO2 saved by cycling.

If the challenge of the above appeals to you then you could make an iphone/android app to do the above and sell it on the app marketplace, hopefully to make your efforts financially worth your investment in time.

Hope that helps!


Any research (or reliable statistics) on benefits of making yourself more visible (blinking light even in daytime, bright colors)? Someone just posted this on our local cycling list serv.

It's about Motion Induced Blindness. Their point was that fixing your gaze on something on the dashboard can blind you to things that are moving (like bicycle near you).

There are some things we can do to help this:

Wearing a bike light even during the day (flashing style)
Wear brighter colors
Maybe bright paint/decals on your bike.

But I wanted to see if there was any research/stats on the subject before I increased the local visual pollution (with my light, etc.)

The following study, carried out in 2009, seems to have attempted to answer the same question:

Kwan I, Mapstone J. Interventions for increasing pedestrian and cyclist visibility for the prevention of death and injuries. Cochrane Database of Systematic Reviews 2006, Issue 4. Art. No.: CD003438. DOI: 10.1002/14651858.CD003438.pub2.

This looks like a meta study, the full text of the article contains links to the various sources they examined and the articles they found.  Their conclusion was that the research is inconclusive: "the effect of visibility aids on pedestrian and cyclist safety remains unknown".

If you go beyond visibility and look at changes you can make to your appearance and their effect on driver behaviour then you might like the 2006 research on overtaking by Dr Ian Walker who has sparked some controversy with his research concluding that cars leave cyclists more room if the cyclist does not wear a helmet or if they grow their hair long.


Replace rear deraileur without breaking the chain I currently have a Shimano Dura Ace 10 speed rear derailleur with a 12-25 cassette. For some hilly rides I'd like to change to a 12-30 cassette.

The maximum the rear derailleur can handle is 28, so I'm thinking of getting a Shimano 105 RD. I'd like to be able to switch between these two set-ups but fear that breaking the chain each time is not a good thing to do.

Is it possible to change the RD without breaking the chain by taking apart the pulley wheels?

Also is it possible to fit a 12-30 cassette on a Shimano Dura Ace 10 speed short cage RD?

You're likely to destroy the derailleur by doing that too many times.

KMC and Wipperman both have 10 speed quick links which are a better thing to do. Note that you'll need a chain big enough for the larger cassette (or, with a quick link have 2 chains).


Flying Pigeon brake pads - change or not I bought a Flying Pigeon 2 weeks back and am having a lot of fun here in Singapore.
The bike was kept in a pretty good condition by the seller although he used it exclusively for photo ops.
This meant that a few practical issues needed to be addressed:

Braking : Braking is a bit of a problem , especially if there is a downward slope. how can I fix this? Is it possible to buy a set of brake pads to replace the current ones
Front Lamp : The bike uses a dynamo rated 12V 6W to power the lamp. The brightness is enough to warn opposing pedastrians, but won't catch attention of those walking ahead of me in same direction.

The wheels are 28" I believe.
Please help.
EDIT
Thanks for the advice guys. I'm trying to learn more about this system now so that I can do some maintenance on it. watching this for starters :Rod brakes on vintage style bicycles. Setting up and adjusting, tips & tricks, using a 1950 Raleigh
Regards

Welp, you have 'stirrup' style brakes that pull radially against the rim and will have limited power compared to brakes that apply opposing forces to either side of the rim. There is a reason this design fell out of favor many decades ago.
You may be able to get better brake performance with the softest, stickiest pads you can find that fit, but the design really limits the performance you can expect.


Bottom bracket for Bottechia 989 Can anyone guess what type of bottom bracket this is?  I'd like to get all the parts ready so I can open and clean it all at once.

It is a Bottechia 989 frame that I bought in Egypt.

You have a sealed cartridge type bottom bracket. You can take it out but you can't disassemble it, clean or service the bearings. If the bearings are running smoothly without excessive resistance leave it alone. If you do need to replace it new units are not particularly expensive.

The cranks fit on square taper or spined interfaces on the axle. The bolt in the crank pulls the crank onto the axle.

To get the cartridge out first you need to remove the crank bolts and use a special tool to pull the cranks off the axle. The cartridge itself threads into the shell in the drive side and is held in place with a locking cup on the non drive side. You need another special tool to interface with the splines in the cartridge body or cup and a large wrench to unthread them from the shell. The drive side thread is left handed.

Chances are you have a standard cartridge with ISO shell threads, and JIS square taper axle. See https://www.sheldonbrown.com/cribsheet-bottombrackets.html and https://www.sheldonbrown.com/bbtaper.html.

To replace the cartridge you need to know it's for a road bike with a 68mm wide bottom bracket shell (check this) and the axle length. Axle length is critical to make sure the chainrings are spaced from the centerline of the bike correctly.


Suntour Raidon 27.5+ 120mm air fork i woke up this morning to my suspension feeling really odd. It is really hard to push down and stays down until I lift my wheel off the ground. What makes it even weirder is that it is making a noise like some air leaking.

What happened and how can I fix it?

The Raidon is an air spring, oil damped fork. It sounds like an internal valve is blocked or stuck shut, and that is resisting fork compression and rebound.

Suntour does provide a range of servicing manuals and videos, but unless you are an experienced bike mechanic you should take the bike to a good local bike repair shop and have them deal with it. Suspension forks have very specific servicing procedures that must be adhered to.


Shimano 8515 question I was wondering if this was a good derailleur, found a specialized bike on Craigslist with this on it.

That says 8SIS (i.e. 8 speed Shimano Index System), a thing Shimano used to mark some of their derailleurs with when the system was still new-ish.

It's a basic Alivio level part -- nothing special, on the mid to low range. You can replace it with any 7-9 speed Shimano derailleur.


Replaced my crackset, chain keeps popping off the small chainring under load Looking for a little lower gearing on my gravel bike, I replaced the crankset with a FSA Omega with 46/30 chainrings, along with a new bottom bracket & chain.

If I stand on the pedals while on the small chainring, I can get the chain to slip & pop off the chainring. This makes starting and climbing pretty rough ;)

The front derailleur looks to be adjusted correctly.

I'm looking for other ideas of what could be causing the chain to pop off, or maybe the FSA Omega crankset is just incompatible with my bike?

Assuming you have a 10sp RD 350 SS short cage (R350 GS seems to be a 9 speed item), you have possibly exceeded the total capacity and are not getting enough chain tension.

Capacity with 48/34 rings was 48 + 36 - 34 - 11 = 39. Capacity with 46/30 rings is increased to 46 + 36 - 30 - 11 = 41. AFAIK, only long cage derailleurs for triple rings have that much capacity.

Do you really need a 30t small ring? Would increasing it to 32t - to decrease the total capacity - be ok for you? Alternatively you could think about replacing the derailleur.


What tolerances should I use for spoke tension when building a wheel I am replacing the rim on my rear wheel with a new one. I've brought up the tension on the spokes close to the final tension by truing / increasing tension / truing / increasing tension.

I've got myself a park tool TM-1 tension meter.  I've been measuring the spoke tension, and they have a deflection reading varying from 19 to 21 or so, giving tension between 85kgf to 105kgf, using double butted 2.0/1.8 spokes according to the park tool deflection to kgf conversion chart.

How close of a tolerance between spokes tension readings should I allow for the final tension?
How should I even out the tension to the ideal tolerance?

This blog post (google cache, original gone) on the Park site suggests a range of 20%, this thread has people saying a range of 1 on the TM-1 is fine (edited in some quotes):

I sort of try to finish within a 0.1 mm error radially/laterally and under 0.5 notch (of the tension meter) of standard deviation for all spokes.
I get DS tension under 1 notch on the park tensionmeter.
Average: 14,25 (notches of the park tension meter) Standard deviation : 0,58 notch

That's what I generally use when building a wheel. I'll look up the chart and get something like 15.5 for a 1200N tension, so I'll aim to have all spokes between 15 and 16, and most of them close to 15.5. With a TM-1 I know my repeatability on measurements is only about +-.25 anyway, so if I measure the same spoke several times I'm likely to see 15.5, 15.75, 15.5, 16... and say "buggrit, that's a bit over 15.5". But for any single measurement I could in theory chase the 15.5 target and go 1/4 turn looser or tighter, squeeze a few spokes then re-measure. But that wouldn't necessarily tell me I'd helped the situation, and might not even be accurate to within the tolerance I think I'm aiming for.
The actual process is pretty repetitive:

get the wheel fairly round, focusing more on up-down than left-right circularity (hops are hard to get out later)
run around and tightening spokes half a turn at a time to get the tension slightly under my target (say 14 using my 15-16 target)
get the wheel true to 0.5mm or so
Then I'll run the tensiometer over the whole wheel to see how even the tension is. If there's a big problem I'll back everything off a turn and try again. Otherwise I'll back off any over-tight spokes a little, tighten the loose ones and stress relieve the wheel, hoping it comes right. Then I'll re-true it. And repeat this step. Again and again, until it's all good.

Once you get the hang of it a lot of those steps will happen once at most. Normally I'll hit each spoke maybe twice with the tensiometer, and possibly a couple of spokes more than that. A good build would be tightening by feel, getting it true with a couple of tweaks, measuring and it's done. But that's very rare unless I'm on my third identical wheel in a day. If I'm fixing an existing wheel I might end up working 4-5 spokes 5 times or more trying to get it right.
One test I suggest you do is just to write down the tension of each spoke on your wheel, then put that bit of paper in a safe place. Then do it again, so you're measuring without looking at the earlier measurement. Then compare the two sets of measurements. That will give you an idea of the variability of your measurements of spoke tension. There's no point trying to get more accurate than that with a wheel, because you're chasing a random number.


Train cycling legs for a long walking trek Cycling is my sport. I'm training for a multi-day ride (four days). Each day will we be hard riding but not too long. The week before the event however I'm going on a four day trek with a 20kg backpack.

I'm happy to lose some form for the event and have a great time treking with friends. However the last time I did a trek like that my legs were toast for a whole week afterwards. The uphills were a breeze but it was the 20km downhill that killed me. My legs are made for pushing pedals, not going downhill!

Any advice on the minimum amount of training to survive the walk and be good to go for the cycling event?

I'm with you on this. My summers often include a mix of cycling and hiking/backpacking, where cycling is the dominant activity.

Two things that have helped me. The major one is to use trekking poles. I discovered trekking poles one summer after breezing through some difficult rides, and then being devastated on a not too serious hike. The poles significantly reduce the leg impact, especially on the descents. The second thing is to cross-train between hiking and cycling; but that depends on your personal time constraints and goals.


Can you use Shimano 11 speed chain pins on a 10 speed chain? I want to purchase a spare pin for my Shimano Ultegra 10 speed chain.  Looking around I can only see 11 speed pins for sale.  Can I put these into a 10 speed chain?

My understanding is that the chain pins for Shimano 10-speed chains are 6.0mm in length and the pins for the 11-speed chains are 5.8mm in length. That is pretty close, but I wouldn't chance it. I also don't know for sure if the pin diameter is the same and I don't have an 11-speed pin to measure.

A simple google search turns up many places where you can purchase the 10-speed pins. Even better - I have to believe that nearly every local bike shop in your area would carry 10-speed compatible pins.


Choosing parts for wheel build on a cargo bike conversion I am using an old Xtracycle Free Radical to convert my hybrid 90s Specialized CrossRoads to a cargo bicycle.

The Free Radical was originally designed for 26” wheels, but many people used them on 700c bikes using disc brakes.

My plan is to stay with the 700c tires, but move to disc brakes because the 26” to 700c V-brake conversion kit was discontinued a long while ago, and the FreeRadical tail does have an area to mount disc brakes from.

My rims are old Araya 700c-PX 45 rims, but years of using the bike with pad brakes has deeply carved out the rims, so I fear that I have no choice but to replace them both in this project to stay safe. In order to cut down on costs, I’m going to build the wheel set and put together the disc brake in the rear. I’m reading Sheldon Brown’s Wheelbuilding site, but I am having a hard time figuring out what components to use to build these rims and the rear disc.

Here are some details about this build:
I weigh about 125 lbs. The Xtracycle can haul up to 200lbs (additional). I doubt I’ll ever haul 200 lbs, I’m mainly going to be getting groceries and running errands with it. The Xtracycle can only take a disc brake with a 203mm rotor. I’m attempting to build this economically, so I’m hoping for decent quality, at an affordable price that is lower than buying pre-made new wheels. I do have access to a bicycle co op where I may be able to harvest used parts.

Do you have any suggestions on what type of rim, spokes, hub, rotor and brakes I should use?

Do you have any suggestions on what type of rim, spokes, hub, rotor and brakes I should use?

For cargo bike purposes you obviously should prefer sturdiness over light weight for wheel components.

A wider rim would allow  you put wider tires which can help with high cargo weight. For 700c wheels, rims that can accomodate tyres of at least 40 mm width are reasonable.

Previously, one would recommend going with bigger number of spokes per wheel in such wheels — 48 if you are really dedicated to find them as not many vendors offer them, 36 if possible, 32 if no other option, and avoid modern rims and hubs with less than 32 holes. However, I am unsure if this advice keeps up with the times, and it may well be that 28-hole rims are as good as 32-hole these days.

For spokes, use the thickest straight-pull available. For nipples, use brass ones.

For hubs, use compatible ones. Given that you don not plan  to spend too much money on the project, just use the best you can find to match the rims and the frame/fork.

I do not think that it makes any difference as of which rotors to use, as even the cheapest ones stop things as efficiently as the fanciest ones, while being only heavier.

For brakes, it depends on the terrain where you would ride this. If the area is mostly flat, I would say any decent modern disk calipers would do the job. If there are prolonged descents, then you'll have to look for four piston downhill-rated options for front wheel. With 203 mm rotors, look after the compatibility — most likely you will have to use adaptors from 160/180mm to 203mm.


Name of a certain modern rear-derailleur part at upper end of pivot Some derailleurs, particularly "old style" drop-out-mounted ones have a pivot whose upper end is a kind of combination joint: it has a bushing that allows the pivot to rotate, under spring action, and that joint also has attachments for the pivot's parallelogram members.

Newer style direct-mount derailleurs (but even new drop-out-mount ones like the Shimano RD-TX55) elongate this upper joint of the pivot into a small member. The rotating bushing is on the upper end of this member (rotating around the mounting bolt on the DM units), and the parallelogram members attach at the lower end of this member.

Does this member have a special name? Is it considered part of the pivot, or are only the parallelogram arms "the pivot"?

For that matter, does the original "combination joint" have a name, and is it considered separate from the pivot?

If it's the part I think you mean, Shimano label it as either the Bracket Axel Unit or the B-Axel depending on if it's the direct mount or standard mount variant.


700c 28er - same as 29er? I thought that all 700c/622 wheels were "29er" compatible or basically the same size; 622mm.

I had the tire off a Mavic Aksium wheel yesterday and was surprised that it is labeled 700c 28''.

Is this a 29er compatible wheel? Is 28'' meant to be the approximate outside diameter on a road tire, and 29'' the approximate diameter of a mountain tire, or am I misunderstanding?

As usual, Sheldon's got the answers.

ISO 622 is the unambiguous way of referring to the following rim sizes:

700c (you see this marketing on road, hybrids; this is from the French system; the c is often dropped, but there are rare a,b sizes)
29"x decimal (you see this on mountain bikes; usually only applied to wide rims)
28"x decimal (particularly in Germany)
28" x some fractions (seems to be a rare Canadian / northern European thing).

700 mm is roughly 27.5 inches, so if you mounted a reasonable tire on it, you'd get around 28 inches (hence the name 28"). For mountain bikes, you'd get a bigger tire giving an outside diameter of 29"+.

In theory, any tire which can be mounted to a rim marked as any above sizes can be mounted to the others, but in practice you want the rim width to be appropriate to the tire size you're mounting.

In terms of which way you should refer to this wheel size, ISO 622 is unambiguous. If its being used on a road bike or hybrid, 700c is also a good way to refer to it. If its being used on a mountain bike with a big tire, 29" is also a good way to refer to it.


New bike wheels dont sit in dropouts perfectly, are washers safe to use? I recently upgraded my road bike from Vision Team 30's to Mavic Ksyrium Elite UST wheels,  However once I got the wheels and put them on, the rear wheel seems to rub on the brake hardware when riding.  When I put the bike on a hanger and spin the wheel, it seems fine, but every time I ride, I can feel resistance, as if I'm riding with the brake slightly engaged.  I messed around with the quick release and found out that even with it tightened as much as humanly possible, The rear axles seem to almost be a little too short, and I think this causes them to sit slightly loose in the rear dropouts, despite the skewer being tightened all the way.  I tried using the QR skewer that came with the wheels, but it is worse than the ones that came with the Vision wheels, so I've been using them, but still have a bit of play with the rear wheel.  From the looks of it, I could throw a washer in between the axle and the frame to have it sit snug, but I'm wondering if this is safe or not? By my estimates, the gap with the new wheels is maybe 1-2mm, just about the size of a washer.

I was under the impression (not knowing much about road bikes) that all wheel axles had the same width, is this not true?

Update: photo showing washer and problem area:

It seems the washer works great.  No more wobble in the wheel, no more rubbing.

could it simply be that the new rim is a few millimeters wider and the brakes are making contact because of that? If the wheel is seated into the dropout all the way, the quick release will have enough force to fully clamp the frame to the hub securely. Check by unclamping the qr, putting some body weight on the saddle with a shoulder and reclamp the qr. Beyond that, mattnz's suggestion above is possible. The whole hub assembly/bearings might be too tight or too loose, which is an easy fix.


Replacing a SRAM Force hydraulic caliper with a new one I'm replacing my SRAM Force hydraulic caliper with a new one, I've drained the old one so there's no fluid in it. When replacing the caliper with a new one how can I put fluid into it? Should I just do a classic bleed or are there special steps to follow for new caliper installation? thanks

This SRAM video on replacingthe hydraulic hose involves removing all the fluid from the system - the situation you are in now. At the end it says to bleed the brake then links to the standard SRAM bleed process, so presumably that's what you need to do.
The standard bleed process is designed to displace all the old fluid with fresh, so the lower syringe must contain enough fluid to fill the system. I think I'd repeat the steps for removing air bubbles a few more times than SRAM suggests to make sure the system is filled properly and there is no air left in the system. If the lever feels spongy you can of course repeat the bleed process.