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geoff
09-28-2011, 09:57 AM
I have a new bike with only about 340 miles on it. I handbuilt a new set of wheels for this bike and ridden with them for about 140 miles. For about the last 20 miles or so, there is a clicking noise coming from my rear caliper brake.

I've taken the wheel and tire off and checked the wheel to make sure it is still true. I've cleaned the brake pads and made sure they were adjusted properly. It looks like everything should be fine.

I was reading Sheldon Brown's site, and he said it could be normal for a new rim to click due to manufacturing imperfections and they should go away on their own. However, I had no click for the first 120 miles, so I am not sure if his advice applies to me or not.

There is no weird noise while riding, it only occurs while applying the rear brake. The brake works fine, except for the clicking noise. What else do i check?

wsbob
09-28-2011, 10:34 AM
I have a new bike with only about 340 miles on it. I handbuilt a new set of wheels for this bike and ridden with them for about 140 miles. For about the last 20 miles or so, there is a clicking noise coming from my rear caliper brake.

I've taken the wheel and tire off and checked the wheel to make sure it is still true. I've cleaned the brake pads and made sure they were adjusted properly. It looks like everything should be fine.

I was reading Sheldon Brown's site, and he said it could be normal for a new rim to click due to manufacturing imperfections and they should go away on their own. However, I had no click for the first 120 miles, so I am not sure if his advice applies to me or not.

There is no weird noise while riding, it only occurs while applying the rear brake. The brake works fine, except for the clicking noise. What else do i check?


State what gear you're running; brand/model brakes, but also, rim, spokes, wheels.

Are you certain the clicking noise is coming from your caliper brakes, or is the noise specifically occurring when you apply the brakes? Every time, all the time when you apply them, or just under certain braking situations?

Kind of sounds to me like it could be rim braking surface imperfections, but since a lot rims today seem to have machined sidewalls, that may not be the problem. Assuming the wheel is true...(I'm not experienced with these things personally, but seems I've read that roughly, a sixteenth of inch, though not perfect, is probably ride-able.) The other thing could be spoke tension or irregular spoke tension. Can't remember what they're supposed to be tensioned to, but there is a spec for that. Too loose would let things move around when they shouldn't be, possibly creating clicks. I've read that some people actually use a spoke tension meter/gauge to set them up.

geoff
09-28-2011, 11:18 AM
They are tektro 545(?) cheapie caliper brakes that came on my madone 3.1. The components for the wheels are Velocity A23 rims, DT Competition spokes and Ultegra hubs. I did use a spoke tension meter and got the spoke all pretty close to the same tension. Also, I've taken the wheels off and recheked for trueness, and they are spot on.

The noise only occurs when I apply the rear brakes, and it seems to only occur when I'm over about 6mph. At really low speeds, I haven't noticed it.

The really strange thing is that there was no noise whatsoever for about the first 120 miles on these wheels.

Alan
09-28-2011, 11:37 AM
Can you spin it up and brake in a workstand, where you can watch what's happening? I would look, listen, and carefully feel closely at the caliper attachment bolt, and at the caliper pivot(s), for any indication of motion, possibly some bind-release-bind sort of thing.

New spokes will 'pop' and 'ping' as they seat, but generally that's done within 100 miles, and it's not a regular noise, just one-off pops.

Have you built wheels from scratch before? Did you learn from a book, or did you get some help from someone knowledgeable? Either way, very cool! And do let us know what you finally figure out on this brake noise!

geoff
09-28-2011, 03:03 PM
This is my first set of wheels. I watched a few youtube videos and read Jobst Brandt's book called The Bicycle Wheel and of course Sheldon Brown's website. It's not too terribly difficult as long as you're patient.

If I spin it in the stand and brake, the clicking is not there.

At the suggestion of a co-worker, I checked the tightness of the bolt holding the caliper brakes, and it needed about half to three quarters more turn before it felt tight. Hopefully this will fix it, but I won't know until I ride it home tonight.

Alan
09-29-2011, 09:33 AM
Just curious, did tightening the caliper bolt make the clicking go away?

Thanks for the wheel building ref's. I'm impressed by the "attention to detail" needed to build a nice wheel!

geoff
09-30-2011, 08:13 PM
If you can true a wheel, you can build one. Lacing was a little bit confusing, but that's where the YouTube vids came in.

Yes, the bolt was loose. I hadn't touched it before, so I didn't even think to check it. Problem solved. Thanks for the suggestions.

wsbob
09-30-2011, 10:54 PM
"...and carefully feel closely at the caliper attachment bolt..." Alan, comment #4

Alan...good one! Looks like you win the cigar. I got so carried away thinking of spokes and tension, etc., didn't even consider the most simple and obvious.

geoff....glad you've got one less annoying sound to bug you in your life. Speaking of wheelbuilding, last winter, I did a fair bit of reading about that. I'm not big on wrenching, but one of my wheels probably needs to have its rim replaced. Maybe I'll sum up the courage and tackle that...this winter.

What I've come to understand, is that maybe the most critical part of the job is figuring out the proper spoke length. There's spoke calculators, but using old hubs, not sure whether measurements exist for them. Might have to measure them myself and hope not to make a mistake.

Alan
10-01-2011, 12:51 PM
I enjoy working on machines if I have the right tools, including a good workspace, and plenty of time. I have trued a number of wheels, even tuned out some rather large 'wows' and replaced a few spokes, but to actually build wheels from scratch I would sure like to use a truing stand and dishing tool. That's my excuse and I'm sticking to it! (for now)

Thanks but no thanks on the cigar, wsbob. ;) And thanks, Geoff, for confirming what was going on.

fredlf
10-18-2011, 04:05 PM
"What I've come to understand, is that maybe the most critical part of the job is figuring out the proper spoke length. There's spoke calculators, but using old hubs, not sure whether measurements exist for them. Might have to measure them myself and hope not to make a mistake."

Old thread, I know, but wth. Most shops will happily calculate spoke length for you if bring in or at least know what exact hub and rim you will be using. Wheel building is not all that hard, just kind of pain-staking and exacting. You have to go slowly and be very patient. Lacing is the easy part (esp. if you Jobst Brandt's book "The Bicycle Wheel"). Tensioning is where all "art" is. My advice, based on the 30-40 wheels I've built, is to use spoke-prep, make sure all spokes start with exactly the same amount of tension/turns, tension very slowly and stress relieve after every tension round.

For learning, I recommend doing a front wheel first. Dish makes rear wheels quite a bit trickier.

Wheel building is incredibly gratifying and fun! I have hand-built MTB wheels that are over 15 years old that are still round, true and strong.