For a studded tire that is available in both 29" and 27.5" which will perform better in snow/ice all else being equal? I"m looking to start winter riding. My soon-to-be bike, a 2018 Devinci Troy Carbon 27 GX 12S, is able to take both 29" and 27.5" tires.

I prefer 27.5" tires, but would I have more control and stability using 29" studded tires for winter/ice riding? (Assuming tires are the same basic model and width).

I realize that 27.5" studded tires are rare. I can only find 2, by Suomi and Schwalbe.

If 29" tires make for better winter tires, why?

Wheel size probably doesn't matter that much, the one that would probably perform better is the wider one with more aggressive tread or the one with studs.

However, once you get to a certain width (I'd say above 3.0) then tires can start to more easily wash out sideways on wet snow, which I get on my fat bike regularly, but not so much on my 29er or 27.5+ bike.

You're right though, about having more options for 29er tires with studs.


Help replacing front derailleur Evening, total newb question maybe but it’s driving me mad.

I have a Carrera Vulcan 2015 model which I bought second hand to aid my physiotherapy. From what I can work out by the spec sheet the front derailleuris a Shimano Tourney FD-M190 (I think, I say that as spec sheet says 27.5 inch wheel which is ).

What could I replace this with? I haven’t got a clue and the lad in the bike shop literally said “dunno” and shrugged his shoulders.

Rear derailleur is a SRAM x4 with a 8 speed Shimano cassette (which could do with replacing (I assume all 8 speed cassettes are the same).

Thank you for listening and any help would be hugely appreciated.

Paul

As far as I can tell the 2015 Carrera Vulcan came with SRAM X4 all round. If the front derailleur is a Shimano unit it definitely was not original. I would guess the previous owner swapped it in. A Shimano unit will have 'Shimano' and 'Tourney' written on it. A picture of the derailleur added to you question will help us provide a good answer.

In general SRAM and Shinano derailleurs and shifters are not compatible because they use a different cable pull ratio (how much cable is pulled to move the derailleur a certain amount).

You options for replacement depend on what front shifter you have. If the shifter was also replaced with a Shimano unit you'll need a Shimano derailleur replacement. I'd avoid the Tourney range and upgrade slightly to something in Altus or Acera ranges. The exact model you want depends on if the the cable routing comes from the top or bottom of the frame.

If the shifter is still a SRAM unit you the obvious choice for a replacement is a SRAM X4 unit as was originally fitted. I don't think SRAM makes these anymore but they are available from Ebay, Amazon etc.


Remove rounded nuts/bolts from wheel on old bike I have an old bike I need to repair (including flat tyres!)
Unfortunately it has rounded nuts on it and can't seem to unscrew them.

Is there an easy non expensive way to remove them without damaging them?

If the nuts are rounded they're stuffed.  You want to remove the nuts but not damage other things, like axles.

I'll assume you're talking about axle nuts, but the same ideas apply to all nuts, bolts, and even screws to some extent.

So your nuts look something like this:

Clean the flats up with a file.  Use a medium flat file and smooth off the lumps of deformed metal in the corners.  Keep the file parallel to the flats and take your time.
Get the right-sized tool.  An axle nut is often 14mm, but that's not quite 9/16" of an inch.  So try the near-size tools.  They should go on snugly and have minimal play
Use a 6 or 12 point socket, or a ring spanner.  There's even specialist axle nut spanners as pictured which work quite well.     .Do NOT use an adjustable crescent!
Leverage - get a length of pipe and slip it over your socket driver handle. 50cm to 1metre should be ample leverage.  Any more than that and you risk damaging the tool.
If that's not helping then stop here, and get some penetrant oil like PB Rust Blaster, or CRC or anything that will soak in and help break up corrosion.  It could be the nuts have rounded off because they're simply on really well.  Also look for pins or any other secondary retainers.  My landy uses tab washers, which are designed to be folded over nuts to hold them from vibrating loose.

So all the easy fixes have failed.  You're going to have to get brutal and your nuts probably won't survive the later options.

Vise Grips or a Pair of Stiltsons, aka a pipe wrench.
Leverage is your friend, but watch the slip-zone should something give way.
Cold chisel works well on larger diameter things, but small nuts not so much.  I'd not bother with this.  The shock of hammering may upset your bearing cones and cups inside the hub and even the headset takes abuse.
If you have one, try cracking the nut in two with a nut splitter
Finally you can get a small 3" or 4" grinder with a cut-off wheel and thin down the nut.  The danger here is slipping and damaging the axle, or the wheel hub, or yourself.  Plus there's hot spitty sparks which can set fire to lubes and oils and cloths and anything.   A dremel tool with a 1" cutoff wheel might work, but the wheels tend to shatter quickly which is also expensive.
If you can't cut the nut off, then consider cutting the whole axle off.  The nuts pictured above would work well because the flange is a good guide of where to cut.  Once the top part of the nut is off, the flange may slide right off at best, or its only got a couple of threads to undo and you have more leverage.  A new axle is absolutely needed because it will be too short, and will have overheated changing its hardness.

Sometimes heat can help, but its also able to cause worse damage.  A steel fork should be fine, but its very easy to overheat aluminium.  Carbon fibre will melt badly or worse it might overheat, loose strength, but look undamaged.  This is the worst case, so only apply heat if your fork is steel, and there are no plastic parts in the area.

You can also use cold, sometimes, to "shrink" metals and break things loose.  I've found that carefully-applied heat to be much more useful.

Once you get the wheel nuts off, consider replacing the axle and nuts anyway.  A new axle with wheel nuts, two cones, and lock nuts shouldn't be too expensive.


Why can my rear derailer no longer shift between all 8 gears? After a low-speed collision with a car. my LBS replaced my damaged rear derailer. Shortly after, I replaced chain and cassette (from a SRAM bundle) and the front chain ring myself, as I've done several times in the past.

After adjusting the derailer while shifted to the 8th and highest gear, so the pulley wheel aligned with the smallest cog, the shifting was smooth all the way down to the 3rd gear. But I was not able to reach 1st or 2nd.

Adjusting the derailer while shifted to the lowest gear, shifting was smooth from 1st to 6th, but I was not able to reach 7th or 8th gear.

My derailer seems to span only 6 cogs.

So far I've tried (without luck):

Cleaned and lubed derailer hinges
Losened both limit screws significantly - to the point where I can push the derailer past smallest/largest cog, without using excessive force
Removed the chain and shifted back and forth, so the derailer can move freely - still only spans 6 cogs when using shifter
Took the bike to (another) LBS who adjusted the cable to it kind-of spanned all 8 cogs, but didn't run properly, let alone smoothly, in any of the gears - worse off than with 6 well-working gears!

What could be wrong? Gear cable? Cable housing? Shifter? - Any help greatly appreciated! :)

It sounds like you may have bent your deraileur hanger.

Looking forward from the rear of the bike, the hanger should be perpendicular to the ground when the bicycle is standing straight up.

Some bikes have replaceable hangers.... For others there are tools for aligning bent derailleur hangers....  Absent the tool and depending on your comfort/mechanical skill level it is possible to align the derailleur hanger with a large adjustable wrench by removing the derailleur and rear wheel and applying gentle force to return it to its perpendicular position.

If it is bent to severely, I highly recommend taking it to a shop.


Is it worth getting a suspension seat post as a cheap alternative to full suspension bike? I'm planning a ride from Birmingham to London on the Grand Union Canal (UK), which will be quite bumpy for most of the 145 mile distance.  I have a front suspension bike and can't afford a new full suspension bike.  Do suspension seat posts actually work?  If so, I'll get one of them.  Can anyone recommend a good model?

You might find a suspension seatpost to be comfortable, but a suspension seatpost is not a substitute for a full suspension bike.  The purpose of a suspension seatpost is purely comfort (though as mikes mentions, not everyone agrees that they achieve this goal), where as the purpose of a full suspension bike is first and foremost control.  Suspension on the wheels helps them stay on the ground over rough terrain, which a suspension seatpost will not do.  Any extra "comfort" is simply a side benefit.

If you're looking to smooth out your ride, the #1 thing you can do is lower your tire pressure.  You will lose some efficiency when the ground is smooth, but if you're already riding 145 on a bike with a front suspension, I suspect efficiency isn't your top concern to begin with.


Inner tube for 27 x 1 1/8 bike I am new to bikes and was wondering if there is a difference between inner tubes for a 27 x 1 1/4 bike and a 27 x 1 1/8 bike. My bike has 27 x 1 1/8 tires but I wanted to use 27 x 1 1/4 inner tubes since they are easier to find.

Should be fine in almost every case. The exception would be tubes that say "700x32-35 (27x1-1/4)", or anything else that has a 700C range where the starting number is larger than 28. That would be bigger than you want. (Would still probably work, but it wouldn't be ideal.) In other words, there isn't usually a difference, but only in the sense that most 27x1-1/4 tubes have that width on the top end of the range they cover rather than the bottom.

If you can't find one that just says 27x1-1/8, use anything that has 700x28 in its range. That's the answer you won't go wrong with. It's a tire for a different and more common rim size, but the tubes for it are interchangeable with 27x1-1/8. Make sure to get the right valve type.


How can I troubleshoot battery issues on an electric bike? I've got an electric bike with a GWA Easi-A36 battery (10.8Ah, 33.8V). The bike has a GWA electric motor.

When I turn the motor on (on the handlebar "computer"), the battery indicator tells me the battery is empty. However, when I test the battery using a voltmeter it says 37.3V.

I could buy a new battery, but that's 570 USD - and possibly only to find out that the battery works fine.

As far as I can see, there are three "main" components involved :

The battery
The motor
The handlebar "computer"

How can I best troubleshoot a battery and / or motor on an electric bike to find out what's wrong?

Its likely a mismatch between the computer and battery pack. 33.8V is not a common voltage for E-Bike Lithium. 36V is more typical. The nominal voltage of the battery is probably 36V based on the model number.  It is possible a cell in the battery pack has failed,but form the specs you have given I don't think this is likely.

Batteries are made from cells - lithium batteries are nominally 3.6 or 3.7V/Cell. A 36V battery will have 10 cells, at full charge voltage will be around 41-42V and fully discharged around 32V (the last 10% causes the bulk of the volatge drop).  A nominal 33.8V battery will have 9 cells, with a full charge voltage of around 37-38V and a full discharged voltage under 30V.

If the computer is using battery voltage to determine State of charge, it will think your battery is flat when it is charged.

To confirm this diagnosis, you will need to find out the number of cells in the battery, and the details of the bike computer.  Also form fully charged (ignoring the bike computer) haw far can you ride before the engine cuts out?  If you going a reasonable distance, close to expected, then its just  mismatch. If you going a short distance, then either the battery if faulty or there is a mismatch and the computer thinks the battery is flat so shuts down the motor.


What are the spokes of the Kona Rove ST I have a Kona Rove ST 2019. The specs only say "Spokes: Stainless Black 14g". How do I know the precise reference so I can buy some spare ones online?

Possible duplicate of How do I know which spokes to get for my wheel?

Best way is to measure the hub and the rim, or at least to know hub model and rim model.

Probably quicker to take off one spoke and measure it, but please note that on the back wheel they are of different length, depending if they are on the gear side or on the non-gear side.


Replacing fork and hydraulic brakes I had a 2012 29er Giant Talon that got a bit trashed a few years back, so I bought a new bike which was recently ripped off.

As a result I am currently trying to get my Talon in working condition again, I have to replace both the hydraulic breaks. I was considering replacing them with the original Tektro Brake Disc Draco Hydraulic, but thought this might be a good chance to replace the fork as well.

I am now worried about getting into compatibility issues between new forks and new brakes.

Kind of a dumb question, but I was wondering what the best way to check compatibility is between these two parts when I am looking online, as well as if there are any suggestions for a sturdy, medium end hydraulic brake and fork that are compatible.

The brake (not break) / fork interface will be standard post mount and is the least of the problems. Adapters are readily availble so you won't have a compatibility problem that cannot be sorted for a few $$.

The other issues to watch for when switching forks from that era would be the steerer - Talon was probably 1/18th straight, but tapered are now far more common. Its possible to get adapters to fit straight forks into frames built for tapered, but not the other way round.

You will also need to match your wheel, or more accurately, axle. Likely the Talon had a 9mmQR, forks now comes in many variations of QR and though axle.

Therefore you want to find a disc compatible fork fork with the same steerer and axle mount as you already have.


Carrera Virtuoso Rear Derailleur hanger bolt hole with HeliCoils? So, I broke a Shimano Sora rear derailleur last night... Ouch, there goes a load of cash...

What had happened was the hanger was bent slightly inwards, yet was functioning fine, so I rode it home. Came to a slight bump in the road whilst in first gear, and then the rear wheel spokes decided the derailleur looked tasty, caught the mech and bent it all the way up, over, in front of and then below the chain-stay. Long story short, it broke. Just in case you hadn't gathered. :P

I've repaired bikes for years, but I've never come up to this part; Can I use HeliCoils to place into the bolt holes for where the hanger itself is meant to meet? I cannot bring myself to part with this frame as it was my best friend's, and he had died after riding this bike in a small criterium near me, I brought it up to scratch, offered it to the family to help pay for funeral costs and they decided I should be the one entrusted to look after and care for it. I screwed up big time.

Theoretically, HeliCoils should ('should') work in this application; If it works holding brake calipers on cars, it should work for this. But, would there be any other way to fix the threads (which are warped and stretched, not even a thread chaser would work on it!) so I can still use the same bolt size? I don't want to have to bodge it together with a bigger bolt size in a larger, re-tapped hole. In fact, I'm not even sure THAT would work, either.

Could I put a big tack weld in where the hole is and then drill the weld out to tap a thread into? (After rubbing the paint back and all, though Aluminium is a pain to weld) I've never tried anything to do with frame/fork work directly, I'm used to fixing bikes, not frames, if you know what I mean by that.

Any help would be great, and I'm curious if HeliCoils would actually work. Cheers.

It's a little unclear, but I'm gathering that you've got a hanger that secures with two little screws, probably M3x0.5, that thread into the frame, and those frame threads are toast with some distortion/warping of the holes also present. If so it depends on how enlarged the holes are - the oversize tap that would come in the M3 helicoil kit has to have enough material to cut into to do its thing. Beyond that, there should be no issue.


Shimano integrated shifter/brake: Cantilever compatible with V-Brake? I have to replace an integrated shifter/brake, right side, 7 speed Shimano STX.

Is a shifter for V-brake (e.g., this) compatible?

Bobotech recommends here not to do such replacement.

This question is related to my broken shifter spring one

Generally road caliper and cantilever brakes are not compatible with "V"  brakes levers. You have a few basic options. Find a single shifter and reuse your brake lever, find an integrated shifter for canti brakes,( likely a rare find), up grade your brake to a "V" brake. Your local shop may help with some used parts. In my area used brakes go for around $10. This is for arms, pads and a cable noodle. You should see an improvement in braking with the "V" brakes.


How to change the seat clamp on a dropper post? While trying to tighten the screws on the seat clamp on my wife's bike, I overtightened one of the screws, damaging both the screw and the seat clamp. (I had used a torque wrench and had set it to the recommended max torque of 3 Nm, but it didn't click/release on one of the screws for some reason - I'll be more careful next time...)

I now have a replacement seat clamp, but was wondering what the easiest way to replace the defective one was. The complexity is that the bike has a dropper seat post, which means that I'll have to pull the seat post out of the seat tube and then try to remove/reinstall the new clamp over the seat post cable. On my wife's bike, the cabling is routed internally in the frame.

Since the seat post remote's cable is already frayed out a bit at the end at the remote's end, I want to avoid removing the cable from the remote - I'm afraid that it will be difficult to get it back into the remote...

Is there an easy way to replace the seat clamp in this scenario? My current preferred way would be to unscrew the remote from the handle bar to give the cable enough slack for pulling the seat post out of the seat tube. Am I on the right track, or is there a better way?

As you already noted you have to unscrew the remote from the handlebar and push the hose/cable into the frame so you can pull on the dropper post. Afterwards you just remove the screws from the seat clamp and pull it over the cable. Install everything backwards and you are good to go again.


Catching train on return trip in Sydney Australia I'm building up to do Eastwood to Kariong and within the next two weekends I am going to ride Eastwood to Berowra.

Because there isn't much for me to do when I get there and I don't want to ride the whole way back I am thinking I will catch a train back to Eastwood. Considering the road travels alongside the train line it will convenient for me to jump on the train.

I am wanting to find out how much trouble this is:

Does taking a bike on the train in Sydney usually go without problems if it is done on the weekend?
Any problems carrying a bike through the turnstyles and down onto the platform?
Where is the best place for me to stand in the carriage once on a Sydney train with my bike?
Any issues with the security guards?

Since I do this style of trip fairly regularly, I'll answer, even though my experience is in New York, USA:

Taking a bike on regional/commuter trains on the weekend is usually very fine, so long as it is not a holiday.  Which days the train operator considers to be holidays are posted on their website, though not always very easy to find.  In New York at least, the full PDF schedule has a few trains marked as off-limits to bikes, and a few marked as especially good (able to carry many bikes).
Turnstiles are not used for regional rail in New York, though they are for the subway (metro).  Where present, the booth attendant can open the handicapped gate for you and your bike--facilities for wheelchairs are generally a boon for cyclists, which leads me to the next point.
Here, since there are no dedicated bike racks on board, we lay our bikes up in the spots designated for wheelchairs (assuming no wheelchair users are there, of course!).  Not every car has such spots, but every train does.  We look for the wheelchair symbol on the outside of the train to choose which door to enter.  Often there are folding "jump seats" in these areas which cyclists fold up to make room.  It is important (even technically required, though not enforced here) to use two small elastic "bungee" cords to secure your bike against against the wall (where there are sometimes small hooks or loops for the purpose).
No issues with transit employees regarding bicycles in my experience.  They've mostly been quite accommodating here.

One additional note: some train operators require a "bicycle permit."  My local example is the MTA Metro North system, which charges $5 for a lifetime permit.  You can pay after boarding the train, or buy it in advance.

Your mileage may vary quite a lot since we're on opposite sides of the earth, but maybe you or someone else will find this useful.  My experience is with the Long Island Rail Road, MTA Metro North, and New Jersey Transit systems.


Shimano Nexus 3 stuck on lowest gear I have a bike with Shimano Nexus 3 gear, and it's stuck on lowest gear. However, if I move shift pin that changes gears it changes the gears. So Nexus itself seems to be working, but the pin is not returning to correct position when going to higher gear. Is there a spring broken that should return the pin to correct position, and if so, how should I fix it? New spring? New wheel? Lot's of WD-40?

Had same problem. Bell crank on the end of the axle is worn. Replace the shifter housing on the end of the axle. When worn, it won't push far enough on the shift rod. Cheap fix.


Fulcrum Racing 5 LG freehub replacement - drag I just replaced a Fulcrum racing 5 LG free hub.  Once it was all together, it seems a bit tight.  With the bike on the stand, when I spin the pedals, and release, the pedals continue to rotate. So the free hub is not spinning as freely as I would expect.
I did not disassemble the entire axle and hub; I just removed the worn free hub from the drive side, and replaced it with a new free hub.  So, no changes, other than the free hub itself.
Will it loosen up? Is this related to the pre-load on the non-drive side of the axle?  Anyone have any experience with this?

After a couple of email exchanges with Campagnolo technical services of North America, I've confirmed that I correctly installed the new free hub (but you should do this carefully, as the pawls and/or spring can be damaged with too much pressure or twisting).  The technician confirmed that the new bearings could be a bit stiff as they "break in", but that things should loosen up appropriately.
So, I will put some miles on and confirm this as the answer once things loosen up.
Edit:  After about 100 miles (160 K) the bearings have loosened a bit and the wheel is spinning without dragging along the crank.  So, I believe that in this case, the new fulcrum freehub body did indeed need a break-in period.
Also:  as long as your wheel was stable on its axle before replacing the freehub body...don't mess with the pre-load mechanism.


Why would someone steal my rear derailleur and hanger? Yesterday while I was at work someone stole the rear derailleur and hanger off my bike. Everything else left alone.

Why would someone steal a derailleur? Seriously. Of all the parts.

Some thieves will intentionally disable a bike so that it can’t be ridden home. Then they’ll come later in the day or evening with the appropriate tools to finish the job.

Often they’ll steal a wheel or your seat or handlebars. But if you had those secured with security bolts then the derailleur might be the next easiest thing to steal that would totally disable your bike — and on many bikes you just need a hex wrench to take it off. And you can put it back on just as easily when you’ve taken the rest of the bike.

Otherwise, no clue. It may have been done by the same thieves who stole an inner tube from a bike here on SE while leaving the tire and rim.


I'm evaluating how to best match a new handset and rear wheel to a vintage rebuild My first bike after  move to Japan. Picked up an old 520 Cro-MO frame by Tsunoda - Grand Prix , minimal rust and decent paint. It had some old Suntour VX derailleurs, aluminum-far-too-narrow drop bar with suicide brakes, Sugino 165 cranks, lowbar Shimano friction shifters, Araya 27x1.25 aluminum rims (close to true) and a freewheel 6 speed -Suntour  -  125mm rear end.

I decided for now to go with the original wheels (new tires, tape and tubes - repack bearings & replace rear axle), but swap the old freewheel for a new  Shimano 7. front derailleur to Sora double, rear derailleur to Tiagra  RD-4601 (10 speed), keep friction shift for now, replace handlebar, breaks Tektro Long.

So here is the part that I am very interested in hearing from people about; I wanted to work with the bike for a while, get a good feel before settling on a handset (this will be the biggest cost and from what I can tell the most constrained decision)which includes deciding to change wheels or build a new rear 27 to go with modern 10 speed index shift or get a handset to work with the 7 speed or what?

Tsunoda are/were a mass manufacturer in Japan somewhat similar to Schwinn in the USA. Most of the bikes they produced were low end though they did make some mid-to-upper end models (I once had a Tsunoda made Lotus branded frame from the early 80s). I believe the brand is still around in the Japanese market but now mostly making folding bikes. Your bike sounds like a mid-range bike based on the SunTour parts. It's a very nice sport-touring bike. It's nothing special though arguably better made than comparable bikes of today. In their day the Japanese made mid-range bikes were almost always better built than comparably priced European bikes and often better built than many high-end European bikes! Japan still make amazing bikes though exchange rates keep them from being exported the way they used to be.

The rear end is 126mm, not 125. 126mm was the standard up until the late 80s when 8 speed cassettes were introduced. The 126 spacing, VX derailleur and SunTour 6 speed freewheel likely dates your bike to the late 70s to mid 80s. The 27" rims while rare in most of the world by this time were still very common in Japan.

Not sure what you mean by "handset". Are you talking about the STI brake levers that also act as shift levers? I'm assuming you are since those are now the norm. If so, there are a few things to consider:

You will need to respace the rear end of the frame to 130mm. This should be done by a bike shop and even better by a frame builder. 10 speed cassettes and modern hubs are spaced to fit 130mm frames. It's not an expensive or difficult process but does take a certain degree of skill and specialized tools.
Yes, you would need to build a new wheel to convert to 10 speed. Your wheel uses a freewheel hub. This means the cassette cluster also houses the freewheel/clutch mechanism. Modern 10 speed drivetrains use a cassette hub in which the freewheel/clutch mechanism is part of the hub and the gear cluster simply slides onto the hub. You can still find 27" rims, especially in Japan. Unless the rims are very worn out I'd probably stick with the original rims and just change the spokes/hub. Panaracer still make some nice 27" tires.
Ideally, you would also replace the chainrings. Modern 10 speed drivetrains really work best with the special chainrings designed for them. These rings have cut away teeth, pins and ramps designed to help the chain move smoothly from one ring to other (especially from small to large). You can often buy a crankset with rings for not much more than just the rings themselves.
You will need a new chain. 10 speed drivetrains require a much narrower chain.

One last note: the 27" Araya rims you mention are almost certainly a hookless design. Most rims have a small lip design to help hold the tire on when it's inflated to high pressures. These rims almost certainly do not. I would advise against inflating the tires past 75 psi/5.2 bar.


What is the black plastic circle on wheel axle nut? I have been seeing a black plastic part on the nuts of the wheels. My bike also has this. I think I have seen this only on old bikes. Does it have a name and purpose?

Some close up:

Those look like packing pieces used to stop the axle ends from punching through the cardboard box partially assembled bikes are delivered in.

I'd imaging they are being used to stop the axle nuts getting scuffed or scratched.


Is there much of a difference between flatland and park/street frames? I am a newbie at biking, and I've been wanting to get into BMX for a few years, and I can now since I actually have some money. Primarily I've been wanting a 20" BMX bike with front and rear brakes and a detangler, but looking around on danscomp and a few other places there aren't too many in my price range. Anyways, that's not really what my question was.

Since I'm new to this, I've been reading a bit about frames, sprockets, brakes, etc., and found out there is a frame that is specifically for flatland riding, here:

But, when I look at a lot of tricks online (I've just been using Google Images) and look up 'flatland tricks / bikes' or 'bmx tricks', most of the pictures are just using the typical frame with the straight bottom tube. So finally, is it really necessary to buy a 'flatland' frame, which would just cost more and be harder to find, or just use a typical BMX-style frame?

Since you are new to BMX I would find a good local shop that specializes in BMX. In my area the three largest conventional road/MTB shops don't carry BMX. We do have two very good shops that only sell BMX and skateboards. So don't be dismayed if the first shop you check has nothing you want. If you can't find one, stop by the local skate/bike park and see what everyone else that is riding. Ask where they go for service, repairs or parts. Like mountain biking, BMX has bikes specialized for specific styles. The frames and components are designed for the style. From what I have seen Flatland bike are designed for slow speed tricks on flat terrain. This is where handling and light weight are more important than the ability to survive big air. The info I can find seems to point to you able to do flatland tricks on a standard BMX frame. If you try to do some dirtjumping or big air tricks on a flatland frame it's lightweight frame and components wont take the abuse for long. Since you are new, your style and preferences will change. I would look for a good used bike, this is where a good local shop can help.


Alfine 8 gear crunch Occasionally under load when taking off on the flat, I would get a crunch, then it runs smoothly.

After reading the other post I had tightened the wheel nuts but this has not fixed the issue. I have checked the yellow lines align also. It occurs in variety of gears. The bike was only 1 week old before it happened and it was next day after ride in rain.

I live in NZ and bought the bike in Australia, so taking back to vendor is not a option. For interests sake it's a focus planet belt drive.

I'm not sure what kind of 'crunch' you experience, but I have a possibly similar behavior of my Alfine 11 hub when I switch gears and I apply some force on the pedals.

Resting my foot on the pedal while standing and shifting is enough for the internal gears to not complete the shift, when I start pedaling, the gears engage in the speed I shifted giving a noticeable crunching noise.


How do I re-attach a crank that has fallen off? I have already read My crank fell off, how do I re-attach it?, but it did not answer my question.

I was biking up a hill in first gear, and I felt my left crank was a bit loose. Never having had problems with my crank before, I kept going. Sure enough, the left crank fell off.

It appears there is a square hole in the crank which the axle goes through (which is also square). This is held on by a hex bolt about half an inch long. The bolt says "CH 12.9" on the head.

Below is a picture of the crank where it attaches to the axle. Note the threads. There is supposed to be a circular piece that goes into them and holds in the bolt. Unfortunately, it must have fallen out before the crank fell off and is probably in a ditch who knows where now.

However, I believe damage has also been done to the crank. I'm not sure if you can tell from this image, but there are dents in the hole, probably from the axle. I have tried to put the crank back on the axle, but I find it incredibly difficult. I decided against a hammer with a wood block because I'm not sure if that'll make it worse.

That's my problem. Here's my question:

Is this repairable? If so, how do I go about it?

First off, got to a bike shop and get a new crank bolt.  They're a fairly standard item.

Can't tell for sure if your bike had "self removing" bolts or standard ones, but it doesn't matter that much, a standard style should fit.  The large threads in the crank arm are for holding a removable trim plug over the bolt (or holding the "self-removing" part of a self-removing bolt) and for facilitating a crank remover (which is kind of not needed at this juncture).  You can ask for a new trim plug at your LBS, but it's not really needed.

Once you have the bolt, you can try reattaching the existing crank arm.  It will need to be really tight -- look up the torque specs on the web if you have a torque wrench, otherwise just get the bolt damn tight.

But once a bike has been ridden with a loose crank arm the arm is usually damaged beyond repair -- likely it will keep working itself loose, and will eventually damage the crank axle (if it hasn't already).  So you probably need to replace the arm, and you might as well replace the crank cartridge at the same time, since it's probably cheaper than the new arms.

(So I'm guessing you've figured out by now that you should never ride a bike with a loose crank arm.)


Schwinn 1979 12 speed I purchased a vintage Schwinn 12 speed recently, the bike had been re-painted and I cannot figure out the model?

Here is what I know the head badge says 3219 meaning the bike was mfg on the 321 first day of 1979 or Nov.17th 1979 this is confirmed by the mfg stamp on the rear lower wheel mount of the right side of the frame G1179, if I understand correctly the "G" means the bike was produced by Giant Bicycles in Taiwan, and the 1179 confirms the November of 79 manufactures date. On the left hub mount there is a serial number of 318514?

Everything I find on serial numbers says that there should be a LQ in front of the number, LQ meaning again the letter codes used for a Nov. of 79 mfg period? There is not? When looking up the number I get no results unless I use the LQ prefix?

LQ318514 comes up that the bike is a Chicago made Bicycle, yet the date stamp says Giant? Is there any way to cross reference the serial number and find out the Model of the bike? I believe that it is a Approved World Sport, except the Schwinn catalogs do not show the World Sport as a 12 speed?

I think you're right on the age based on this document,
http://thirtythree.org/projects-unconverted/Lowrider%20Bicycle%20Restoration/Identifying%20Schwinn%20Frames.pdf

G from Taiwan, in 1979.   As the document mentions, even though the date code is 79 it could have been used in 1980's line up.

The 1980 catalog shows a couple 12 speed's
http://schwinncruisers.com/catalogs/1980.html

Only the Voyageur 11.8 says it's Schwinn-Approved making it made most likely from Taiwan.
Without any pictures or remaining decals this may be the most likely model.


How many freewheel thread sizes are there? I'm buying new freewheel and noticed that not every freewheel can be screwed onto my hub because they have different thread sizes.

For example: I've found the following thread size specifications:

M30x1
M35x1
"big" 1,37" about 34.8mm
1.375" x 24 tpi

I've read that some type can only use 16 or higher tooth so in case it is important, my current hub has a 16 or 18 tooth bmx freewheel screwed on.

Questions

How many are there and what are they called properly?
Will any work on some other type?

The ISO freewheel thread standard is 1.375" x 24tpi

Most freewheels I have encountered have been ISO.

Some hubs use "British" threading at 1.370" x 24tpi

If you use an ISO freewheel on a British thread, it will work, but you should check there is enough thread engagement to avoid stripping the hub. The trials-oriented retailer TartyBikes suggests 9 thread is enough (Trials bikes often run a freewheel at the crank using a 1.370" x 24tpi thread)

Italian freewheel thread is 1.378" x 24tpi: Fine on ISO, but even shallower thread engagement on British hubs than ISO on British. Still viable though.

French freewheel thread is 1.366" x 25.4 tpi or 34.7 x 1mm

If you tried mixing 24tpi with 25.4tpi at the same diameter, the threads would be strained and with enough engagement would eventually jam. As the French diameter is smaller, an Italian, ISO or British freewheel will just about thread on but will have very little thread contact and will slip under load, blunting the hub threads.

Metric BMX is M30 x 1[mm] or 1.181" x 25.4 tpi. This is a small enough diameter that all the above sized freewheels will be obviously sloppy on an M30 hub.

I've never seen an M35 x 1 freewheel, but it seems close enough to French that it should work.

Mini-freewheel (Which I've seen on some DMR Revolver hubs) is 1.18" x 24tpi

Mini-freewheel and Metric BMX are close enough to cause trouble. The diameters are within tolerance but there will be strain on the threads and the hub threads will be less snug if you later replace the freewheel with the correct item.

Praise be to Sheldon.


Adjusting disk brake pad positions I have had experience on a couple of mountain bikes when I could not adjust the disk brake caliper positions far enough left or right to keep the pads from rubbing the rotor a little. Is this common and/or normal? Is there a something I'm missing, or should I just bend it a little?

You are not alone. These brakes require constant adjustment and are not fit for purpose. The recommendation is to upgrade to Avid BB7's or a hydraulic system. Read the litany of complaints:

http://www.mtbr.com/cat/brakes/disc-brake-system/avid/bb5-mechanical-disc-brake/prd_414627_1507crx.aspx

Before you tear them off the bike in disgust you may want to take a read of the Park Tool instructions for adjusting Avid mechanical disk brakes:

http://www.parktool.com/blog/repair-help/avid-reg-mechanical-disc-adjustment

This explains quite clearly how the brakes actually work - the outer pad moves whereas the inner pad does not. The disk gets pushed across by the outer pad to hit the inner pad. Note that the more expensive BB7's allow more adjustment and that the even more expensive hydraulic systems work differently, pushing both pads out to meet the disc rather than just 'bending it across'.

Good rim brakes are better than cheap disc brakes and your bike unfortunately has the latter. I recommend that you upgrade the brakes to the best mechanical system you can afford rather than spend any more time trying to adjust what sounds to me to be a flawed product.


Can I use Giant Talon as a road bicycle? I bought a Giant Talon bike and I got thinner tires.

Can I use it for road and streets now?

Can I use it (Giant Talon) for road and streets now?

Yes you can. Here's your bike (if you have a 2020 Talon 2)

There are some good reasons to use a mountain bike as a road touring bike. Here is one example:

And they make fine commuter bikes.

Sometimes people will put drop handlebars on their mountain bike for better aerodynamics. Sometimes, as you have done, people will use narrower smoother tires.

It's all about trade offs
A pure road bike will be more aerodynamic and be configured (weight, riding position, gearing, etc.) for a higher top speed.

A mountain bike will give you more ruggedness, (given the condition of roads in some places this can be a big bonus) a lower top speed, and more comfort. If this meets your needs you will be happy.

Ride what you have and learn
At the end of the day ride what you have and learn what does and does not work for you and adjust along the way. Saddle time is the best way to learn.


Is a used 1998 LeMond Buenos Aires worth $450? This is the bike I'm interested in buying: http://www.bikepedia.com/quickbike/BikeSpecs.aspx?year=1998&brand=LeMond&model=Buenos+Aires.  The bike is in good condition upon inspection and a test drive.  Is it worth $450?

What things do I need to look out for when buying such a bike?  If I were to get it, what should I look out for when using it?

It's a well speced bike, Reynolds tubing is top quality. Given the 1998 price tag of $1300, I would say the current price is good. It will be harder to ride than a modern bike, but not by too much.

Watch out for rust around the bottom bracket covers and cable stops. Early model carbon forks can wear also. It's 8 speed, so still easy to buy chains and cassettes for.


Should I put grease under the lockring on my cassette? I take my cassette off the bike to give it a good cleaning a few times a year and have always put a good amount of grease under the lockring. I am not talking about repacking the hubs, bearings or anything like that, just some grease to fill the gap between the lockring and the sealed bearings that are deeper down inside the freehub.

I've seen some references to greasing the threads on the lockring, but nothing about grease under the lockring. Without the grease does dirt/rocks/grass/mud get into that gap?

If the bearings are sealed (so dirt can't get into the bearing), and there isn't an interface (two surfaces rubbing together), than lube is probably not needed.  Adding lube may actually create a dirt-trap as more dirt sticks rather than just getting in there and falling back out.

The threads, certainly.  Packing in behind the lock ring?  Not so much.


If you buy and install a brand-new chain, but never clean or lubricate it, what will happen? When you buy a new chain, it comes lubricated with a factory-installed grease-type lubricant.  This lubricant is similar to hot wax.  (Reliable sources — including Sheldon Brown, Shimano, and others — seem to agree that you should not deliberately remove this factory lube.)

Imagine that you own a low-end 21-speed bicycle, which you bought second-hand.  You use it for commuting in a big city — in warm, dry weather only.  You've bought and installed a brand-new chain.  If you never clean or lubricate your chain, what will happen?

(In my experience, the bike seems to keep working for numerous miles without squeaking.  But I wonder what's really going on behind the scenes, and what the results might be.)

Please assume that you do replace the chain whenever it's stretched by more than 0.5% (1/16"), and that you complete most other recommended bike maintenance on schedule.  The only maintenance you skip is chain cleaning and lubrication.

Higher friction (comparing to properly lubricated chain) between chain pin and inner plate will make groove in pin surface faster, resulting in chain prolongation (a.k.a. chain "stretching").
Non-lubricated chain will be more exposed to corrosion.
Higher friction between the chain rollers and the chainrings will make the chainrings wear down faster.
Higher friction between all chain components will add avoidable resistance.
People on the street will look at you with embarrassment and compassion because of noise.


What are the consequences of a chain that is the wrong length? I changed the chain on my bicycle before doing any proper reading on it, and I did not check whether the chain was the correct length. It seems to be working ok... but what could potentially go wrong?

If the chain is too long then in some gear combinations (e.g. small/small) there will not be enough capacity in the dérailleur to pick up all the slack, so the chain will be loose.  At an extreme case, the chain could sag and come into contact with the chainstay.

If the chain is too short then in some gear combinations (e.g. big/big) there will not be enough chain to span both gears and go through the dérailleur.  In this case it might not be possible to change to this gear, or doing so could damage the rear mech/mech hanger.

In a bike with rear suspension, there also needs to be sufficient extra chain to compensate for chain growth when the suspension compresses.  Running too short a chain could mean shifting to big/big is possible, but compressing the suspension when in this gear damages the rear mech/mech hanger.

Typically there will be a range of chain lengths in which the gears will function correctly and if the chain is only a little too short/long problems would only become apparent in poor combinations such as big/big and small/small


How do I work out tube and rim strip size I have a Schwinn Men's Volare 1200 Bike, 700c. Recently had a flat. I am confused. What size tubes do I need to buy? And also the rim strip snapped. What size rim strip should I order

You need to know what caused the flat first (recommended reading here); it may merit replacing the tire itself depending on cause.

The tube will be 700c x a-b where your tire size is between a and b.

The rim strip needs to be matched to the rim width. See this question to measure it. Depending on why the rim tape snapped, you may need to make some adjustments to the wheel itself.

If you take the wheel+tire to your local bike shop, they should be able to sort you out with this very quickly and even install the new tube and rim tape quickly for some nominal fee.


Upgrading from 9 speed to 11 speed on Giant Defy 3 If I were to upgrade from a complete Shimano Sora R3000 9 speed groupset to a complete Shimano Ultegra 6800 11 speed groupset (excluding hub) on a Giant Defy 3, do I need to get a new hub too or can I just reuse the old hub?

I have never changed the groupset before since I never had the need to change it so I do not know what else do I need other than the groupset itself but since my old groupset is dying on me, I have to change it soon and I though why not upgrade it to an 11 spread instead of simply just replacing the old groupset to the new one

On road drivetrains the freehub body was made a little wider for 11 speed to accommodate the extra sprocket (34.75mm for 8, 9 and 10 speeds to 36.75mm for 11 speed), so unfortunately the 11 speed cassette cannot be mounted on your hub.

I believe there may be some hacks to get over this, but I cannot provide any information.

Edit: Some 11 speed cassettes will fit on an 10 speed freehub body, specifically larger sizes where the large sprockets can overhang the inboard end of the freehub body, I believe.

You could upgrade to the 10 speed Tiagra group which would still be a substantial bump up in performance and reduction in mass.

It could be said that going to Ultegra is not worth the cost as the rest of the bike is still at Sora level. Also, separate groupsets are relatively expensive, and you have to take into account the cost of installation. Very often it's a better idea to simply buy a new, upgraded bike and sell your old one.


Fix up old road bike or buy new one? Coming back to riding after a long layoff, my Cannondale R500, purchased around 2000, according to the local bike shop, needs a lot of work - new wheels, cassette, chain, cables. Also replaced stem with a new taller one so I don't have to bend down as low.

LBS is saying the tune-up/restoration will be around 400 and offered a new entry level Giant for around 650 and won't charge me for the work they've already done on the old bike.

Not sure what to do. The Cannondale rides fine to me, but to be honest, I haven't put that much mileage on it recently so haven't really tested it. I'm a casual rider, planning to do long rides 3-4 times a month and a century or two this year.

My options are:

1 - Pay for whatever work they did and fix the bike up myself. Don't have a lot of tools and wondering if I did do my own work, I'd wind up wasting a lot of time and paying for tools I don't have.

2 - Have bike shop restore Cannondale, hope it holds up.

3 - Buy new bike.

I don't need a great bike, not picky, don't need the latest and greatest - just want something that will be maintenance free-ish for the next 10-15 years. I can afford a new bike, but I rather use the money for other things. And it just seems like a waste to abandon the Cannondale.

Any suggestions? Thanks in advance.

If you are coming back from a long layoff, I'd fix the Cannondale, then if you keep up riding in the future, spend some time considering if you want to upgrade and what to. It's never a good idea to be choosing a new bike under pressure to get riding.

Make sure the things the repair shop wants to replace are really needed. Cables and housings - yes that's a good idea and relatively inexpensive, but you could do that yourself.

Chain and cassette - make the shop prove they are worn out to the point of needing replacement. If not ride them until the do.

Definitely get the shop to explain why exactly they want to replace the wheels, and what they want to replace them with. You might be able to get a better deal on the used market through Craigslist or Ebay.


What size rotor does the Cannondale CAAD10 2015 have? I have a Cannondale CAAD 10 disc frame and a pair of BB7s that are 160mm rotors.

They do not fit because (I think) I need post mount spacers.

What size rotor does the frame expect, and hence, what size spacers do I need?

The frame comes stock with 160mm rotor in front and a 140mm rotor in rear and uses a spacer for the front post mount only.

From this link, it looks like you need the 20p spacer, which Avid says is OEM only. However the spacing dimensions are 12.5mm top and 7.5mm bottom. You can probably find spacers of those dimensions to mount it without the OEM spacer.

I have the same bike with a 160mm rotor in front and I can confirm the dimensions are 12.5 top and 7.5 bottom and it looks like spacers would work as well.

Here is what the spacer setup generally looks like - 160mm with OEM spacer on front, and 140mm mounted with no spacer on rear.


What does it mean - can be made into a double? Sugino Single Speed Arm Set 175mm Black 130mm

In the description it says: RD2 can be made into a double with double bolt sets.
Can I use these crankarms on my 2 front - 8 rear speed road bike?

What other parameters I should research before buying it?
(130mm BCD, 110mm bottom bracket)

You need a JIS bottom bracket (ISO may work, but ideally you'd want JIS) of the appropriate spindle length for the correct chain line on your bike.

You'd have to buy a set of chainrings for a double and the bolts for a double chainring in order to use it as a double.


Will speed/cadence sensor work with 650c bicycle I plan to use speed/cadence sensor, however my bicycle wheel size is 650c.

I guess, there are no problem about cadence.

But for speed (wheel speed sensor), will it work correctly?

With common digital cycle computers, wheel size shouldn't be an issue as you can configure them to work for any reasonable tire size on the market.


Tube valve cap keeps breaking For some reason, my valve caps keep breaking. I'm not sure if it happens while I ride or while my bike is not in use, but often when I take the caps off to fill the tubes before riding, I find one of the caps has broken in half like in this image:

What could cause this?

Other info: I fill my tubes to 95 psi

You're simply overtightening the valve caps. These caps do nothing to keep the air in the tube, so there's no need to do them up tightly at all. In fact most road cyclists just throw them away instead of using them.


What is a shimano ispec shifter? I know what a shifter is but I could not find a definitive answer on what an ispec shifter is or how is it different from a regular shifter. For example the 2014 shimano deore groupset says it has ispec shifters and ispec ready brakes.

I-spec is a Shimano-proprietary mounting system for Shimano parts. Its supposed to make mounting and adjusting brake+shift levers faster and easier by putting them on one mounting clamp.

I couldn't find a blurb on what it does / how it operates on the Shimano website, but the equivalent for SRAM is SRAM Matchmaker, which from their website:

"The MatchMaker X clamp is more than just a clamp. It’s like having Martha Stewart tidy up your cockpit. Since each clamp accepts up to three controls, you can put everything from your XLoc suspension lockout, your SRAM shifters and AVID brake levers as well as your Reverb XLoc remote, all on two clamps. Short of genetically engineering longer thumbs, it’s the ideal way to put everything within easy reach. Just like Martha would."

If you're running a mix of SRAM MatchMaker and Shimano I-Spec components, you can use a Problem Solvers MisMatch adapter to mix them up.


What is the average reduction in air pressure for a mountain bike tire? I've noticed that my mountain bike tire looses air, not because of a leak, etc., but just naturally as time progresses.

Does anybody know the average psi loss over time for a mountain bike tire and tube?

Just the average for a 29" wheel.

Continental tire ( they make tubes as well ) states that their tubes loose about 5 psi per week and suggests topping them off on a weekly basis.

This information is not published but they will tell you as much on their support line if you speak German.

For a tube and tire combination, the tube is designed to hold the air in, not the tire and is the point of loss to consider.


Can't find any replacement original chainrings (SG A-52-42-30) . What can I use instead? I have an early 2000's Giant OCR 2 roadbike (3x8 speed) with worn out chain rings on the Shimano Sora FC-3303 triple crankset. The original rings are the SG A-type, 5 bolt, 130 mm BCD in 52T-42T-30T sizes. All I can find are used ones, and I'd prefer not to change the crankset. Can I just drop the A-type originals and go with new ones in the same bolt pattern and BCD that are close (ie 53T-39T-30T)? Thanks

Yes, you don't have to use actual Shimano chainrings, you can use 'third party' brands.

There are a few manufacturers that produce replacement chainrings in a wide range of BCD measurements and tooth counts, so you be able to get exact matches.

If you do decide to change gearing, derailleur position and chain length will need to be changed, but you should probably be replacing the chain at the same time as as rings anyway, and also checking at the cassette for wear and replacing that if necessary.


Are torpedo 3 gear shift cables a standard or are there different sizes? I want to replace the cable of a bike with an old sachs torpedo 3 gears internal hub and I'm not sure what do I have to buy.

In this related question the answer is that there are some differences between latter sram hubs, but, is the cable the same?

When I search some for that cable in some shops they only write that it is for torpedo/sram but anything about different models.

Mine look like this:

In my experience the normal shift cables (and housing) work fine, but there is a special end cap on the cable that fits into this hollow rod-like thing in the lower left corner of the picture. Normal cable end caps do not fit into this, because they are too thick. The original part made is out of brass and squeezed on with pliers. It's the center piece in this picture:

You can also find some hollow brass rod in a model train shop or similar and clip off a small piece. It just has to fit inside the rod.


Unicycling for over 60s Are you an over-60 unicyclist with insights you would like to share, about anything from getting started to getting off?

Here are a couple of insights about getting started, that might be helpful.
1.  Use walking sticks for a few weeks or months - you will know when to throw them away.
2.  Get good body armour - I particularly recommend Kris Holme gloves.  You will also need knee and elbow pads, and a good helmet.


Adaptor for Garmin Edge 530 out-front mount to a Go Pro I am using the Garmin out-front mount for my Edge 530 and I am looking for an adapter that ables me to mount my Go Pro underneath the out-front mount. Does anyone know any method? Hacks?

P.s: I know K-Edge is making mounts but first I'd like to make sure there are no methods to use my original Garmin for this.

Also, found that Edge 530 mount is different that Garmin out-front mount you can buy on Garmin's website. The latter has four screw thread and as you can see mine doesn't.

It looks like you can get screw in adapters for Go Pros that thread into existing out front mounts from below. So if your out-front mount has metal screw threads already present, check underneath and see if you can get an adapter that will fit below to hold the Go Pro.

Otherwise, no hack can hold the weight of a Go Pro wobbling on a cantilever and given the cost of buying a new dedicated mount vs the cost of replacing a broken Go Pro, the only thing to do is get a proper mount. If you can afford to replace broken cameras you can afford to buy the proper mount in the first place ;)


Why does my front brake cable push out of my brake lever? Why is my front brake cable getting pushed out of my brake lever? Is a component of the lever itself broken?
Crashed into a pole the other day, busted the front brake. Brand new to both riding and repairs, so bear with me here. I purchased a new cable + housing to replace the front brake entirely in the hopes that will clear up this issue, but I still want to know what exactly is happening when I press down on my brake lever to cause the cable to push forward? (see video) Thanks for any insight.

The lever is not broken.
The lever's job is to pull the cable away from the brake.
There are springs in the brake that should pull the cable away from the brake lever.
The cable housing should allow the cable to move back and forth with as little friction as possible.
Since it was working before the crash it makes sense that something was bent, kinked or damaged restricting the cables ability to move. Your hand is able to overcome the friction when you pull the brake lever but the springs on the brake are not strong enough to pull the cable back.
It boils down to sticky cable or weak springs. Chances are it's the cable because a crash usually does not weaken springs.
From the video it looks like you have a v brake

Things to check: You may want to disassemble the cable from the brake to isolate the problem.

Make sure the brake arms are moving freely but not sloppy. The mounting bolts should be tight without restricting movement of the brake arms.
Make sure the cable can move smoothly in the cable housing and in the cable guide.

Any cable housing kinks, hard turns, or incorrect cable installation will restrict cable movement. You want smooth bends and low friction along the whole route.
Sometimes a little silicone spray inside the housing helps even when the cable housing is lined.

Sometimes you can increase brake spring tension with the balance screw.


Can I use Shimano 105's brakes with vintage bike? Complete newbie here, looking for better stopping power and less rusty calipers.

I have a Nishiki Custom Sport with Dia Compe brakes and I was wondering if I could use the Shimano 105 5800's on them.

I've heard conflicting comments on the compatibility with the SLR design and the pull ratio (they state you need "ST-5800, ST-6800 or ST-9000 STIs for correct leverage ratio").

I kind of understand it, kind of don't.

My biggest concern is safety so that's what I'm trying to gauge at (that and the recessed mounting).

Thanks!

For many years, all brake levers had a cable pull for either traditional sidepull/canti/u-brake brakes or linear pull/mechanical disc brakes. There were small differences between levers but essentially every lever across all bike genres in one camp would work with every brake in that camp. When Shimano came out with their under-tape shift housing routing STIs, they changed their brake lever pull to a higher number, putting it pretty much in between the two existing classes. These levers and brakes are designated Super SLR and they include most of the current Shimano brakes.

It's more cable pull. What that means is if you pair Super SLR levers with conventional sidepull brakes, you'll have more rapid arm movement and nice crisp brake feel but less leverage and less power. If you pair Super SLR brakes with conventional levers you'll have the opposite: more leverage but mushy feel and less arm movement, forcing you to have the starting position of the pads very close to the rim if you're going to avoid running out of lever travel.

I don't really recommend doing either. The danger of the former is inadequate braking power, and of the latter it's that it can be easy to run out of lever travel, which is also a safety issue, plus the lever feel is poor.


How to remove the visor of a POC Trabec helmet? The title says it all. I feel like I'm missing something, but I can't find help anywhere on Google, and I don't want to break the visor.

Here's a link
http://www.pocsports.com/us/products/trabec/10501.html

You sure that's removable?  On the POC website, it lists that as "Adjustable visor", not "removable visor"...


How do I make my frame water tight? I am trying to remove the rust from inside my steel frame. There are, however, a few small holes in various places along the frame. Any tips on how I can make these water tight so that I can fill it with vaporust and leave it overnight?

Don't make your frame water tight. That will only make your problem worse.

It's unfortunate to see a frame go bad due to internal rust, but it needs to remain unsealed.

The reason for this is that moisture will find its way in and needs a way out. Even if you never ride in the rain, condensation of water vapor alone will allow liquid water to accumulate inside the frame.

Most frames (I believe) have small drain holes near the bottom bracket for this reason alone.

Here's a nice little post from Gunnar about why their frames have drain holes:
http://gunnarbikes.com/site/2012/06/draining-your-bike/


Is it ever legal in the USA not to have two brakes on a bike? When using a bike on a road in the USA, is it ever legal not to have separate brakes on the front and back wheels?

Many places have adopted the Uniform Vehicle Code language.  It currently states:
 12-706. Brake required Every bicycle shall be equipped with a brake or brakes which will enable its driver to stop the bicycle within 25 feet from a speed of 10 miles per hour on dry, level, clean pavement. (FORMER 11-1207(c)).
The goal of the UVC is to have consistent laws between states, counties, and municipalities.  It doesn't entirely work - often the process of changing the laws is too complicated, so many outdated variations exist.

In 2006, Portland, Oregon saw an interesting challenge a similarly-worded law.  A cyclist was cited for failure to have two brakes, even though the fixed gear on their bicycle allowed them to meet the requirements of the statute.  (Ridiculously, the previous UVC phrasing that the ORS statute is based on doesn't even require the ability to stop, only the ability to skid.)  The judge and ticketing officer's contention was that a brake must be a separate device.

Meeting the UVC phrasing is your best bet for a US-wide policy, but definitely review the local statutes for the places you will be riding if you are concerned.


Why is my fixie so very hard to pedal? I recently got a fixed gear bike and I rode it about 5 times. I live in an urban part of the city. I've never rode a fixie before or know much about bikes in general and I knew it would be difficult to ride a fixie since it's only one single gear and you can't stop pedaling.

I did notice how hard it was to pedal at first but after a few blocks I would get so tired I'd have to get off the bike to rest, especially against the wind sometimes. Now when I ride it takes a lot of leg power to go but then I become so tired after riding for a little bit. Is this normal? Does it take getting used to riding a fixed gear? Or is there something wrong with my bike.

I just think it's not right that a bike that a lot of people claim to say that it's the best easy to ride bike can make me unbearably tired after riding it for a few blocks. I just want to know why this is happening and if it's normal.

There's not really enough information in your question to tell for sure what the problem is, so let me just list a few possible explanations that come to mind:

As others have noted, your gear ratio might just be too high for you (since you say it takes a lot of effort to get going).

You can take your fixie to a bike shop and have them swap the rear cog for a bigger one and see if that helps.  While at it, you can also have them check for other problems, too.
Something (like, say, the brakes, if your fixie has them) might be dragging against the wheel(s), slowing you down and making you work hard to keep going.  Or, just possibly, there might be something wrong with your wheel bearings, causing the same effect.

There's an easy way to check for this: just flip your bike upside down, give the pedals a quick spin with your hand, and see how long it takes for the rear wheel to stop spinning.  Then do the same for the front wheel, too.  (You'll have to spin the front wheel by pushing on the spokes directly.  Be careful not to let your fingers get caught between the spokes and the frame while doing so!)

On a well-oiled bike with decent bearings and nothing dragging against anything, the time to stop should be measured in minutes rather than in seconds, and there should be little if any noise.  (That goes especially for a fixie, where you don't even have the ratchet mechanism ticking.)  Certainly, there shouldn't be any grinding or scraping noise, and the wheel should certainly not stop in less than ten seconds.
If you're used to freewheeling bikes, you might be unconsciously trying to slow down your pedaling after you get up to speed.  On a freewheeling bike, that lets you relax and let the bike roll along — on a fixie, it brakes the bike.

There's no simple fix to that, other than switching back to a freewheeling bike.  If you want to keep riding a fixie, you'll just have to unlearn that habit.  Fortunately, simply with enough practice, that will probably happen naturally.
More generally, you might just be unused to riding a fixie.  It does require a somewhat different set of muscles and riding behaviors than a freewheeling bike, and so you might initially find yourself putting a lot of stress on muscles you're not used to using so hard.  Your description sounds a bit extreme for just plain unfamiliarity, but it certainly might contribute, perhaps together with an excessive gear ratio and/or poor riding position.

Again, this is something that will only be fixed by practice.  After ruling out (or fixing, if necessary) all the other issues, just keep riding regularly and see if it starts feeling any easier.  If yes, you're making progress, and should keep practicing until you can ride your bike comfortably.
Also, make sure to check your riding posture.  A poor posture can make riding a lot harder than it needs to be.  This is true also for freewheeling bikes, but it's particularly true for a fixie, since there you can't just stop pedaling to rest your legs.

In particular, check that your saddle is not too low, as that seems to be a common error.  Ideally, when sitting on the bike with the pedal is at its lowest position (i.e. pointing at 6 o'clock), your knee should be just slightly bent.  (An angle of about 25° short of straight seems to be commonly recommended.)  If your seat is too low, you get less power on the downstroke, and have to expend extra energy to lift your leg on the upstroke, making your legs tire faster.


MInor (I think) dent in top of Orbea Alma top tube - frame ok or no? UPDATE: My lbs mech / owner (same guy) looked at it this AM, says it is good to go, 'ride the hell out of it', he 100% backs it up. And FWIW re: the specifics of this frame and why it's purely cosmetic, he tells me that the top of the top tube, in that area, isn't the load-bearing part (the sides of the top tube are where the material's beefed up and takes the load). Which makes logical sense to me, for this frame anyway (I wouldn't speculate about other frames, I think frame-specific knowledge is key here). The sides of the top tube show zero signs of the impact, no bending / warping, etc etc. Good to go.
Anyway, thanks to all for the input, much appreciated! Ride on...
-cw
2015 Orbea Alma alum frame top tube, looking front left to back right. This pic gives the best angle on the contour - the sides of the top tube feel unaffected by this dent, and you can see from the black center line bisecting the tube that the majority of dent is on the left from the left shifter pod, so what you see here is the worst of it I think. Any general impressions regarding whether I have killed this frame or not would be much appreciated, thank you -

Just off the picture I'd say it's fine. Aluminum is more durable than many people think (you know they build airplanes out of the stuff?!) That said, I would carefully look at the areas where the tubes are welded together. Use a bright light and look for any small, hairline cracks in the paint. Most of the aluminum bikes I've seen fail usually snap at the welds (outside of horrible crashes of course)


Panniers or rack bags for photography equipment Currently I am cycling a lot with a backpack (specifically a chrome citizen), whilst the bag is brilliant it's just not big enough for everything I'm carrying, and with a lot of weight in it it hurts.

I've just bought this rack, and I'm looking to invest in a new set of panniers or some form of rack bag for my bike.

On a day to day basis I'm carrying at least one camera body (at the moment a big heavy Canon 1D body), a large telephoto lens, a wider lens and a flash. On top of this I have other items, such as my bike lock, a pad of paper and a small ThinkPad laptop (~12 inch), it would be nice to also have a change of shoes if possible.

I'm looking for some panniers which will:

Fit in all of my camera gear

Keeping it relatively safe, and dry within reason (i.e. no monsoon)

Fit in my other day to day items.
Ideally I would like to be able to take a pannier full of my camera gear straight off the bike and use it while shooting, then pop it back on and set off with minimal fuss.

What would best suit the above? I should probably add I'm in the UK.

I found a picture of how I did this! You can see the firmer, black foam with foil that I used on the outside, and the bits of softer foam that I used to pack everything in. The flap poking up covers the top when the pannier is closed. This photo is from when I was putting it together, so the contents is not well arranged. I make a simple frame so I could use the pannier as a handlebar bag so it got the benefit of the suspension fork.

I started out with an Ortlieb front roller, which is a smallish squareish pannier. I had a 300D + 70-300/5.6mm at that stage, so it was also fairly small. I got a sheet of foam about 30mm thick and carefully cut and folded it to make a box that just fit into the pannier. I added an extra layer at the bottom, since that's where most of the shocks come from. Then I cut more bits of foam to nest the camera and lenses. Basically set it up the way you'd set up any other camera bag, and arranged so that opening the pannier let me lift the camera out eaasily. Obviously this filled the whole pannier, so on tour I ended up with two full size rear panniers plus that front one. But the camera survived 10,000km or so of riding over several years.

With a larger camera you will need a larger pannier to start with, or sacrifice some of the padding. I suggest getting a large pannier, and making a padded camera bag out of foam to occupy the top half of the pannier, then making a cloth bag to hold that so you can lift the whole camera out easily to access the rest of your stuff. I'd probably keep my d lock on top of the camera round town so it's easy to get to.

The foam I used was house insulation foam with foil on one side. That worked well to stiffen it and make it more wear resilient - otherwise getting the foam box out of the pannier would have inevitably worn away the foam (I used the pannier for other things too). So a cloth cover would do the same thing, and should be easy enough to make as it doesn't need to exactly match the shape of the foam.

If you're looking for a commercial solution I doubt you'll have much luck - I've never seen anything. The best would be a small-ish camera backpack to hold most of the camera gear, then a pannier with everything else in it. That gets most of the weight off your back, but the expensive bits still benefit from the suspension effect of your body.

What I use now is a Crumpler camera side-bag that looks a lot like their bike courier bags but has a fuzzy interior that catches velcro, so I can use padded camera bag dividers to slot camera gear into it. It was easier to add the courier strap to a camera bag than convert a couier bag to camera gear (but it's not a great courier bag if you're on and off the bike all day).

For touring I have a custom recumbent bike with a special bin behind the seat to hold my camera backpack. I have a Desley bag that holds a laptop or a 1D body, but it's not quite high enough to hold both easily. It does, however, max out the cabin luggage size on most airlines. For getting onto the plane I usually put the camera around my neck, often with a big lens on it to bring the bag under the weight limit).


What are the benefits of *rigid* lefty fork? I know there is already a discussion about suspension lefty forks. However, that post completely avoids mentioning of their rigid counterparts which also can be found in the wild.

Below is a couple of photos of rental bikes commonly used in Singapore.

[While looking closely at the second picture, I have realized that there is also just one rear dropout!]

Searching through the net gives other examples of rigid leftys:

EDIT Added more examples.

Vintage 1910's bike:

Somewhat's newer one:

So, what's the deal with them? What are advantages, and there must be some disadvantages (like less compatibility with fenders, hubs, rim brakes etc.)?

One obvious advantage for most lefty bikes is

You’re able to change the tire and tube without taking the wheel off the bike. So wheel adjustments and repair can be made without interfering with the disk brake rotor. This is especially useful on rear wheels as you also don’t have to take off the chain.

In the case of these rental bikes, I suspect that the real reasons are:

Most everything on these rentals that can be made non-standard is — from the head tube diameter to the axle width. This slightly lessens the risk that the bikes will be stolen to be stripped down for parts.
Branding and theft reduction: The bikes are highly visible and recognizable even if they are repainted


Extending integrated carbon seat tube Can I just cut the carbon seat tube, cut a vertical slot for compression and use a conventional seat clamp to hold a seat post in it?

That is unlikely. The inside of a frame is machined/molded to a specific size for the seat post. An integrated post is not finished internally. Also, it is unlikely that the internal and external diameters of the post/frame/clamp would match well enough to be ridden safely.

Seat post fitting is a zero tolerance game, and they are dimension-ed to the tenth om millimeters. You would have to be beyond lucky for that to work out.


Is it okay to buy a cycle from a new brand? I'm from India and I was looking to buy a bicycle for some really long commutes and fitness rides. I'd mostly be doing paved roads with the occasional gravel/dirt. Some reading told me that I should be looking for a hybrid. So, taking my budget into consideration, I've rounded up two.

Triad X3: https://www.choosemybicycle.com/en/bicycles/triad-x3
Montra Downtown: https://www.choosemybicycle.com/en/bicycles/montra-downtown-2019

I guess the Montra is superior here but I didn't really like the sporty graphics and its more expensive than the others. The differences are the dual disk brakes, the Shimano front gears. How important are these? I love the Triad but it seems like they are a new player in the game and I couldn't even find a single review for the X3 online. I was wondering if its okay to go ahead and buy it cause it seems like all that Triad makes is the fork, frame and the handlebars. Most of the other parts are same for the Montra and the Triad. Could someone please guide me as to what to consider and whether I should go for the Montra?

I'm a noob at buying a cycle. Is it okay to buy from a new brand?

At this price category new brands are created all the time and badged onto generic Chinese bikes. There is next to no difference with regard to quality between brands. While 16k rupees (about 200 £|€|$) may be a lot of money in India, it is still a bit below the costs of a bike of reliable quality.

Shimano tourney components are a good sign in an inexpensive bike. However, there will be cost savings in other parts, like cranks, pedals, bearings, and brakes. For example, the pedal threads and square taper interface of cheap cranks tend wear out and fail quickly. Pedal and head set bearings seize or get loose.

This is not necessarily the case for your bike. If sales margins are low, the bike isn't necessarily a dreaded 'BSO' (bicycle shaped object). Yet, learn how to identify one:
[BSO identification for amateurs
[Is KCP a trustable bicycles Brand?

Unfortunately I cannot recommend how to get a better bike for not much more in India. Where I live a decent and simple one costs about 2 times as much. There is a large market for used bikes of good quality that cost about as much as the bikes you posted.

You might want to search for India on bicycles [SE] we had a number of similar questions.


Light for Tubus rear rack I recently received a Tubus rack that I am happy with.
In the instructions there is a wide rear light with a double point attachment.
I want one of those big lights - can someone tell me of one?

see light in this

This appears to be the one in the diagram you linked:
http://www.amazon.com/D-Toplight-Rear-Light-Design-backlight/dp/B000NW65U4/

That one requires external power from a dynamo hub, though I have seen references online to a battery-powered version of the same light.  The same company, Busch & Müller, makes a few others with the same mounting system.  In general you can find these things by searching for "European" style taillights, as they are popular in that region (but not in the US).  Here's one that works on batteries: http://www.amazon.com/4D-Toplight-Permanent-Tail-Light/dp/B0051WTS0A/ (the Senso model is similar but adds an auto on/off capability based on ambient light level).

Here's another that fits the same mounting holes but with a very different design (for use with a dynamo hub only): http://supernova-lights.com/en/products/e3_tail_light2.html

Finally, some taillights have available mounting plates for 50mm rack mounts, such as this: http://ecom1.planetbike.com/3108.html or this: http://www.amazon.com/Cat-Eye-Tailight-Rack-Mount/dp/B002P793U4


Replace S-RAM S7 gear hub with something better I have an SRAM S7 gear on my bike, and I'm not content with it. I find it more or less impossible to get the adjustment right. Supposedly I just have to leave the shifter in position 7 and then assemble the outer part, but that doesn't always hit the spot and the result vary from working as it should periodically, to grinding, to not shifting when it is supposed to. Furthermore the hub is constructed just so that if the chain fall off it gets stuck on an elevation next to the cogwheel, from there it is impossible to get off without picking off the rear wheel.

Point of case, I want something better. I'm looking for reliability and low maintenance. Preferably something that fit's on the same frame. I'd like at least a 5 speed gear, but don't care much for more than that, the current 7 seems a bit overkill.

I'm willing to pay what reasonable quality costs, realizing that what I paid last time probably wasn't enough.

I also wonder exactly how hard it will be to replace the parts, I'm a bit split between doing it myself or paying a shop.

What should I get? Any other advice for my situation?

The cheapest option is probably to buy a whole new wheel off the internet. The Sturmey Archer 5 speed with drum brake is my first choice (www.sturmey-archer.com/products/hubs/cid/4/id/33) - costs about 140 pounds for the hub from SJS in the UK. The advantage of the Sturmey hub is that it's designed to work in various frame spacings so you just remove a couple of spacers and it'll work. They're rumored to be quite robust but I haven't tried the 5 speed, only the 3 and 8. But the brand is good (was UK, now Taiwan, which seems to have lifted the manufacturing consistency a bit).

If you can use a disk brake on your bike the Shimano Alfine 8 is a good option, about $US400 with a cheap brake by the look of it. (do not get a Nexus hub, they were a bit of a learning experience for Shimano). They're available with a disk brake as an option, so it comes down to what your bike frame will accept. If it's got an internal brake now it'll almost certainly accept the drum brake, but if it'll take a disk the Alfine is a slightly nicer hub.

With the Alfine you'll probably have to spread it to 135mm, as (from memory) there aren't any spare spacers you can remove. The SA with drop right in. But if your frame is steel you will almost certainly be able to just spread it the 5mm to take the slightly wider wheel. If you're not comfortable doing that a bike shop or framebuilder will be able to "cold set" (ie, bend) it for you. With aluminium or composite frames that's not an option.

(I don't have enough points to embed the third link, sorry)


Measuring for and buying new MTB tyres I'm slowly upgrading things on my 26" Scott Aspect, I now need/want to get some new tyres.

I think the tyres on there at the moment are 26 x 2.1

Firstly, is that 2.1 Inches? - what are these things even measured in!?

Secondly, I'd like to maybe go for a slightly wider tyre, say 2.25, how and what should I measure to ensure there will be clearance?

Thirdly, does anyone have experience upgrading tyres on these kind of stock MTBs - whats the limit size wise, should I just go for like for like?

Any tyre recommendations also welcome.

We can't recommend a specific tire, also there are very similar questions already on this site but i will do my best to answer your questions.

First: it is indeed inches, although not all tire are measured that way, it is rather common for MTB tires to be listed as such. Other tires, say road tires are listed in a millimeter* sizing such as 700 x 40*

Secondly: Clearance measurement will be inside the fork/frame triangle, both on the side and the top near the crown of the fork, and between the stays on the rear. It's hard to say from the image but it looks like 2.25" tires would be doable but not much larger, one issue to keep in mind is that if the tire is extremely close to the fork but doesn't rub, it may do so under a big hit or heavy load.

Third: The size limit is decided by two things, inner rim width and frame clearance. It is likely that 2.25" would be acceptable as a 2.1" tire is compatible with inner rim widths from 19 to about 28mm widths. 2.25" falls very near to this, and i would imagine the rims that came on that bike are right around 19mm inner width.

So i wouldn't go any larger than a 2.25" i think it would likely work, but cant tell you for sure without seeing more or knowing more.

Tire choice should be based on you budget, and the type of conditions you most often ride in, whether it be on a trail or tarmac.

I tried to keep this answer short, but their are a lot of more in depth explanations available if you search the site.

Hope this helps


Headset ball bearing size I replaced my chewed up retainer bearing with a rusted but not so chewed up retainer bearing. What happened to the old one was that it was installed backwards and the retainer itself was completely trashed as it was doing the job of the balls.

The new bearing is a bit rusty and it's balls are smaller. However, all headset play has been eliminated and steering is pretty smooth.

Should I get brand new bearings anyway? Are there any practical downsides to running rusted bearings that fit but use smaller balls? Any possible damage to the cup?

Buy and fit new ball bearings.  They're under $5NZ $4US for a set.  Its false economy to not replace them when the headset is open.

Headset bearings are probably best in retainers rather than loose bearings.  They don't roll a lot compared to wheel or BB bearings, and there's a lot of small bearings around a relatively large race compared to wheels.


Why should I prioritize top tube length over stand over height on a CX bike? I purchased a 50cm CX style bike from an online retailer.  After assembling the bike and filling the tires, I found only had around 1" of stand over in bike shorts.  Since I will be commuting on the bike and using it for transportation around town, my preference would be for something with greater clearance over the top tube for the following reasons:

Saftey - being able to dismount quickly in an emergency situation
Clothing choice - I won't be wearing bike shorts when commuting or riding around town
Cyclocross - I do plan on riding the bike off-road, so more clearance would be better on uneven ground.

Now to my question: I emailed the retailer asking for assistance selecting a smaller size, but they "strongly recommend" sticking with the 50cm frame stating it would be "perfect" and that the top tube length is more important than stand over height.
What is the thinking behind this advice?
UPDATE
I kept the bike and am overall pretty happy with the fit. I've used it for commuting, long distance rides and a few races.  It's also survived a collision with a bus and lived to tell the tale.  Luckily, I wasn't seriously hurt.  I can also attest that the stand over height didn't make a difference in that scenario.

Why should you prioritize top tube length over stand over?
Because top tube length affects fit and stand over does not affect fit.
When you are riding the bike stand over does not affect fit.

My CX only has 1" of stand over.
A big triangle is good for stiffness and shoulder carry.
A tall top tube means faster transition to shoulder carry.

I don't get your reasons

1" versus 4" should not affect your ability to dismount quickly.
You ride on the seat - not the top tube.
In a controlled dismount the bike is stopped - 1" is a quick and safe stand over dismount.
If you have to bail because a truck pulled in front of you then lay the bike down - don't stand up.
So your clothes touch the tube?  What is the harm?
How is more clearance better on uneven ground?
When you stop then don't stop over a hole.
If you fall on the top tube an extra inch of clearance is not going to save you as your feet are not going to be under and you are going to be moving.
Even with 2" of clearance falling on the top tube should always be your last choice.


Kid's bike - Can I put 20" wheel on a frame that was meant for 18" wheels? So, my friend's kid's bicycle has an 18" tire that is completely worn down. I'm having a really tough time finding 18" tires on local buy/sell websites, but there are a bunch of 16" and 20". Does anybody know if putting a 20" (or 16") wheel on my friend's kid's bike will work? No gears, just back pedal braking, and a hand brake for the front wheel.

Thanks a lot.

There are several different 18" sizes, and several different 16" sizes. See Sheldon Brown's tire sizing page

If the 18" is the 355mm used by Birdy, and the 16" is the 349mm used by Brompton, that's close enough that it might be possible.

People have converted Birdys from 18" to narrower 20" (406mm) by moving the brake posts (see "brakeboss relocator").

I changed the obsolete 500A (440mm) tyres (and chromed steel rims) on an old Dawes Kingpin folder to 20" (406mm) ones on alloy rims, the widest ones that would fit in the fork to reduce the bottom bracket drop, and was able to find suitable brakes to fit.

But for a typical child's bike, I very much doubt it's worth it.


How long is it safe to store new tires before they degrade in quality? I bought some road tires that were made for flat resistance, but within two months, the sidewalls on both got damaged to the point where I was getting repeated blowouts. I wrote to the manufacturer, and they were kind enough to send me a replacement pair.

In the meantime, I bought some new flat resistant tires to replace the busted ones.

Now I have two new pairs of flat resistant tires, but I only have a use for one at a time. How long can I store a new pair before I have to worry about the material degrading, dry rot, etc.?

(not mentioning the brands here because I don't want to bash the manufacturer that sent me the replacement.)

It depends on the storage conditions. If kept at room temperature, not excessively humid or dry, and kept in the dark, they can be stored for a long time. Oftentimes for years.

Your best storage bet is to wrap them in plastic and stash them in the back of a closet. I've kept high-end tubulars for two years that way and that rubber is much more sensitive to storage/dry rot compared to puncture-resistant tires.


Unknown freehub, trying to source I have a neighbours daughters bike to fix at the moment. The freehub is totally seized. I've removed the freehub from the hub itself, but can't identify it nor have I see any like it. It doesn't have a separate locking screw and screws into the hub itself.

It looks similar to a DMR, Halo, or Sun freehub but it's only a cheap hub. The one that looks closest so far is the DMR. Yet the DMR has what looks like an aluminium bit at the end of the thread:

http://www.chainreactioncycles.com/Models.aspx?ModelID=7685

Pictures of the freehub are here: http://imgur.com/a/V11ef#0

The freehub turned out to be a Formula freehub. I managed to source it from Silverfish UK.


SRAM x9 3x9 with a 10 speed Shimano SXL FC-M660 Crankset Ok so let's start this out by saying I have not a ton of money to work with, and really want to get my bike up and working with little cost as possible.  I have friends that have changed out parts on their bikes and have given me some parts to use on my bike that are almost brand new.

I was given a SRAM X9 3x9 front derailluer and a Shimano SXL FC-M660 10x3 10-speed Crankset for free and I want to use them.

My bike currently has Shimano 8 speed rear derailluer and cassette. I have Shimano shifters also on the bike.  They both work great and don't want to have to change those out.

So my question is, can I use the 8 speed rear parts with the 9 speed SRAM front derailluer and 10 speed shimano Crankset?  And use the shimano shifters?  What would be the major problems?

I would like to just have to buy a chain and use all these parts, and wondering what kind of chain should I use with these three speeds?  8,9 or 10 speed chain?

I know this is dumping a bunch of parts together, but beggers can't be chooser and I would really like to get this to work so I can ride.  My crank and front derailluer are junk and need to be replaced.

Thanks

The main compatibility problems arising between SRAM and Shimano is with the rear derailleurs. The SRAM numbered models (X-7/9/0/X etc) will only work with SRAM rear derailleurs (and v.v). Front derailleurs are compatible (I use SRAM shifters and an XT front derailleur). In terms of the shifters you should be fine.

The only difference I can think of for the front derailleur would be the width of the cage - 8 speed uses a wider chain than 9 speed. I imagine the difference wouldn't be great enough to cause an issue though. In the worst case scenario you might end up with the chain rubbing the front derailleur slightly in the 'extreme' gears (biggest/smallest cog on the cassette).

The crankset again suffers from the width issue. The best thing to do is give it a try.


Milian Pere - Brompton child seat - installation instructions My Milian Pere - mount to allow attaching a child seat to a Brompton folding bike - arrived in the mail today. This piece of hardware attaches to the Brompton. How do I attach a saddle to it so that my son can ride in it, which is why I bought it.

Assuming your son will be sitting on a saddle then you need a saddle with a metal clip that interfaces between the rails of the saddle and the post. They are adjustable so the seat can be almost any angle in relation to the seat post. Brompton make one of the clips but you can probably find them cheaper on ebay, or included with some saddles. See images below:


Hole in fork crown welding seam Some time ago I noticed a clicking noise somewhere in headset area. Noise appears under pressure, also it clicks when I tightening the headset. First thought was that problem is with headset bearings, because steering was like "indexed" in center.

So first what I did - replaced bearings and greased everything. Indexed steering had gone. But clicking noise remained. Yesterday I removed mudguard to check fork for the cracks and found this small hole where fork meets steerer tube. Can it be source for clicking noise? Is it dangerous to ride with it?

That's just a poor weld. Notice there are other deliberately drilled holes in that area so an extra one is not a problem.

Clicking in the headset area is much more likely to be flex between the steerer and stem, stem and bars, or possibly the headset races pressed into the frame. If the click happens as you go over a bump or change force on the bars through pedal strokes that would point to those interfaces as a culprit.


Lifting a road bike by one of the seat stays ok? Is it ok to lift a road bike by one of the aluminium seat stays? Yesterday I realised I was doing this when inspecting the rear derailleur during a ride (front of the bike facing down, all the weight on one seat stay) and afterwards it got me a bit worried that I might have bent/damaged something. Bike is Cannondale CAAD12, total weight around 9kg. Just have no idea how strong these seat stays are and what they are capable of. Thank you for your answers :).

If it can hold your weight while sitting on it, then it should definitely be OK to lift the bike from it.


SRAM Guide brake lever won't return I have an SRAM Guide brake (rear) that after bleeding, the brake lever won't return quickly.  At room temperature, this is barely noticeable, but when the temperature climbs, or the bike is in the direct sun, it takes about 30 seconds for the brake lever to return fully.
This happens every time I bleed it and lasts for at least a couple of weeks.  The front brake, bled the same way, at the same time, has no issues.
At first, I was thinking that there was too much fluid in system and when it got hot, the little bit of expansion would lock up the piston.  However, when I popped the top bleed screw while hot, only a little bit of fluid came out and the lever was still sticky.
I am now wondering if the tolerances inside the lever are too tight.  Once the barrel warms up, it shrinks enough that the spring can't overcome the friction...
Any other ideas?  Should I just give up and try a warranty return with SRAM?

This is typically caused by seals which have become soft and sticky due to contaminates like degreaser.  It also happens over time, and SRAM Elixir brakes are especially known to have this issue.

The Guide series hasn't been bad about this so far.

The solution is to replace all the seals in the lever.  SRAM has a special grease (Avid DOT Grease) for this purpose, or you can use DOT 5.1 compatible grease.  Regular grease will damage the seals.


Does the inner tube affect the maximum PSI? If I have road tires that have a recommended pressure of 110 PSI and maximum of 120 PSI can I safely pump my tires up to that level or does the inner tube effect the maximum?

I currently have the tires pumped up to 90 PSI however the question What Pressure Should I Run My Road Bike Tyres At seems to indicate I should go for the full 110.

It feels when I'm pumping that it would be very hard to pump above the 90 mark and I am wondering if the quality of the inner tube (or a inner tube max PSI) could be the reason. Should I just go for it and try to pump it up to 110 PSI or am I best off leaving my tires at 90 PSI?

The inner tube has no significant effect on max pressure.  The valve stem area is the only area sensitive to pressure, and in general the valve can withstand 200 PSI or better.  (And if you exceed whatever limit there is the result is "catastrophic" failure, not simply the inability to pump in more air.)

What it sounds like you're noticing is the geometry of the pump.  A piston pump has a compression ratio, just like a cylinder in an engine, and the max pressure that the pump can generate is that compression ratio multiplied times the 14 PSI of atmospheric pressure.  In general, pumps are designed either to move a lot of air at low compression ratio to fill low pressure tires quickly, or to move less air at a higher compression ratio to be able to fill high pressure tires at all (though more slowly).

Good quality pumps will be advertised with a stated maximum pressure, and you can fill tires reasonably fast to 80-90% of that max pressure, after which progress will slow to a crawl.  So when you shop for a pump you need to pay attention to that number.