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  1. #1
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    Rim seam making noise when hits brake pad. What to do?

    Thup, thup, thup...goes the front wheel when I brake. Looks like the seam is hitting the pad and making noise. How to fix? Just had a tune up and wheel was supposed to be trued, so that should be ok. Looks good to me.

    Flip wheel around? Tighten/loosen a spoke a smidge?

    What can I do to get rid of the problem?

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    If it's a new problem on an old wheel you might resolve it simply by flipping the wheel. This lets the shoes "ski jump" off the high side silently. Otherwise the solution is to carefully file or sand the area smoother.

    Remove as little metal as possible, and don't worry about getting it perfect. Once you're close, the brake shoes will wear it smooth within a short while.
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  3. #3
    coprolite fietsbob's Avatar
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    Looks like the seam is hitting the pad and making noise.
    Is there an actual offset you can feel? with your finger or
    At any speed, even on the workstand?

  4. #4
    Foward Leaning Attitude rithem's Avatar
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    The last thump in brakes I felt was a dent in brake wall on one of my velocity POS tubular I dented on a cross course, Major (bummer) Tom rims. It was obvious.

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    Quote Originally Posted by rithem View Post
    The last thump in brakes I felt was a dent in brake wall on one of my velocity POS tubular I dented on a cross course, Major (bummer) Tom rims. It was obvious.
    That is easily fixed with a bit of hand skill.

    I'm always amazed at the quality of the equipment folks are using for cyclo-cross these days. Years ago the cyclocross season in the fall was about finishing off the stuff that was no longer fit for the road. Drop that new road wheel into a pothole and dent it, hammer it back to decent, and if it thumps on pavement it's a cyclocross wheel.

    Same with slightly bent frames or forks or otherwise rideable but not fit for the road, components. Rather than toss them into the scrap bin, we rode cyclocross to finish them off. Of course as luck would have it, the most marginal stuff which was barely OK for cyclocross was the stuff that lasted the longest.
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    Quote Originally Posted by fietsbob View Post
    Is there an actual offset you can feel? with your finger or
    At any speed, even on the workstand?
    I can feel it with my finger on the non-drive side.
    The other side feels smooth.
    I cannot see the offset, only feel it.
    Not sure about which speeds. I think it happens mostly on long, hard stops.
    Doesn't seem to happen in the rain.
    There is a few mm trail of brake goo on the rim after it that starts right at the seam.

  7. #7
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    Quote Originally Posted by lungimsam View Post
    I can feel it with my finger on the non-drive side.
    The other side feels smooth.
    Odds are it was always the same way, but the wheel was mirrored (flipped left to right) when reinstalled after the alignment. Before you do anything else try flipping it back the other way. If that solves the problem, slide out the QR skewer and reinstall it with the lever to the left.

    We can go for years without mirroring front wheels because we always keep the QR lever to the left. However most mechanics remove the skewer when doing an alignment and don't think about it when replacing it, so it's 50/50 that it'll get flipped.
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    Foward Leaning Attitude rithem's Avatar
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    Quote Originally Posted by FBinNY View Post
    That is easily fixed with a bit of hand skill.

    I'm always amazed at the quality of the equipment folks are using for cyclo-cross these days. Years ago the cyclocross season in the fall was about finishing off the stuff that was no longer fit for the road. Drop that new road wheel into a pothole and dent it, hammer it back to decent, and if it thumps on pavement it's a cyclocross wheel.

    Same with slightly bent frames or forks or otherwise rideable but not fit for the road, components. Rather than toss them into the scrap bin, we rode cyclocross to finish them off. Of course as luck would have it, the most marginal stuff which was barely OK for cyclocross was the stuff that lasted the longest.
    well like anything this discipline has evolved as you have seen. I worked out the bubble and I still used the wheel for the rest of the season, another friend dented his so badly on a curb that it flat spotted the rim and was not repairable, Velocity just are not as tough as Mavic period.

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    [QUOTE=FBinNY;14621936]Odds are it was always the same way, but the wheel was mirrored (flipped left to right) when reinstalled after the alignment. Before you do anything else try flipping it back the other way. QUOTE]

    OK, I will try this first.

    It is a used bike, that I took in for a tune-up, after partial re-assembly, done by myself.
    Me or the mechanic coulda flipped it.
    Funny thing is, I was wondering which way to have the wheel on because if I line up the direction of the lable on the front hub the same with the rear wheel, then the front rim's sticker is reversed from the one on the rear wheel and vice versa.

    I went with rim label direct-ivity. So will flip the wheel now and see if that fixes the prob.

  10. #10
    Ride, Wrench, Swap, Race dddd's Avatar
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    I suspect that the tune-up artist may have needed to apply some judicious force to the rim to achieve a true condition simultaneous with even tensions in the spokes.
    Nothing wrong with that. Often this is the most-consciencious way of getting a wheel optimized.

    At the same time, non-welded rim seams tend to offset slightly when a rim is given the un-taco treatment, and as a last step in the wheel-work process the rim seam may need to be re-aligned.

    This re-alignment is nothing more than laying the rim on a block of wood like a 2X4 laying flat on the ground with the rim seam positioned just past the end of the 2X4.
    Then, a second 2X4 is placed atop the rim, just to the other side of the rim seam, with a hammer then used to hit the 2nd 2X4 as if it were a drift punch.
    In your case, the correction will be very minor, and should be easy. I would avoid any grinding of the rim seam area however as this immediately introduces a condition of variation of thickness of the rim, and may make an anodized rim unsightly.
    Also I would not worry about absolute perfection beyond that which affects braking feel. Over time, the joint will smooth itself, especially if ridden in wet weather.

  11. #11
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    I flipped the wheel, and silence for the first 5 miles or so. Started fffftt...ffftt....ffftt again while braking after that.
    However, now my brakes are working better. No squeal or Chewbacca sounds when braking. No shudder on front forks when braking. Maybe the rim offset was producing that?

    I mean, as long as it is not harmful/dangerous/damaging to ride on the rim with the noise, should I just ride it out for a while and see if it smooths out on its own?

  12. #12
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    Quote Originally Posted by lungimsam View Post
    I flipped the wheel, and silence for the first 5 miles or so. Started fffftt...ffftt....ffftt again while braking after that.
    However, now my brakes are working better. No squeal or Chewbacca sounds when braking. No shudder on front forks when braking. Maybe the rim offset was producing that?

    I mean, as long as it is not harmful/dangerous/damaging to ride on the rim with the noise, should I just ride it out for a while and see if it smooths out on its own?
    Yes, you hadn't mentioned the rest in the earlier post. Think of a misaligned seam as a curb. Going down is a gentle bump, going up a big jolt. Either the misalignment was there all along and the wheel reversed as I said earlier. Or it happened during the alignment (it can if the wheel is fairly bad, but happens rarely otherwise).

    Regardless, it sounds like it's manageable now, and will only get better as the shoes slowly wear the high areas off faster than the low. What you might now be hearing is a bit of extra bite as the shoes hit the sticky area on behind the seam. This may improve, but it can take a while. You can try using some alcohol on a rag to clean the rim, but don't be surprised if the noise comes back.

    Even with perfect, or welded joints, almost all rims have some unevenness in light braking, so it's something to simply live with as long as it isn't enough to cause handling or control problems.
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    Thanks for the info. It has gotten better, and sometimes I don't hear it now.
    The brakes work great now, too.
    I might flip it back for fun just to see how it sounds on the original side again now.

  14. #14
    bike whisperer Kimmo's Avatar
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    Quote Originally Posted by rithem View Post
    well like anything this discipline has evolved as you have seen. I worked out the bubble and I still used the wheel for the rest of the season, another friend dented his so badly on a curb that it flat spotted the rim and was not repairable, Velocity just are not as tough as Mavic period.
    That blanket statement is utterly meaningless; you need to specify how you're comparing apples with apples, pears with pears, and a whole bunch of other varieties before you can say one company craps on the other with any credibility.

    You could prolly fit Velocity B43s to a monster truck and totally crush a whole pile of light and sexy Mavics in one go. But so what?

    Quote Originally Posted by FBinNY View Post
    Even with perfect, or welded joints, almost all rims have some unevenness in light braking, so it's something to simply live with as long as it isn't enough to cause handling or control problems.
    Unless you want to go for a disc-braked bike... that perfect brake feel has me mulling it over...

    Having switched the sides of my brakes after thirty years has really thrown my bike handling for a loop; brakes Really Matter.

    Another thing I've been mulling over is, tubular tyres + Stan's sealant = practical proposition. Hm, I might be the first guy to build a tubular wheelset on disc hubs.
    Last edited by Kimmo; 08-25-12 at 09:12 AM.

  15. #15
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    Quote Originally Posted by lungimsam View Post
    Thanks for the info. It has gotten better, and sometimes I don't hear it now.
    The brakes work great now, too.
    I might flip it back for fun just to see how it sounds on the original side again now.
    Sometimes problem solving is amazingly simple. You didn't do anything to the joint or rim, but by running it in the right direction resolved the issue. I'd leave it as is, but remember that it's direction sensitive in case someone switches the skewer again.
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    An ounce of diagnosis is worth a pound of cure.

    “Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

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    WARNING, I'm from New York. Thin skinned people should maintain safe distance.

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