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So I've been on a journey to fix a worrying squeaking noise that is impossible to replicate on a stand. When I am cycling, the rhythmic squeaking noise seems to come from the front on the bike, but I am only like 75% sure of that.

I first took it to the local bike shop where the mechanic diagnosed worn out bearings in the front hub, but as he could only fix it in a few weeks, I serviced it myself (the cones were indeed pitted, and I have replaced them, axle and bearings with the correctly sized identical ones). When listening to the hub through a screwdriver, it is revolving very smoothly now.

It didn't resolve the problem with squeaking, even though later the mechanic confirmed that the hub is now perfect (took it to the shop again as I ran out of ideas), but he didn't suggest anything else.

Here is what I can tell for sure about the noise:

  • As mentioned, it is impossible to replicate it on the stand.
  • Front hub as the source of it can now be ruled out.
  • I still think it's the front of the bicycle that is squeaking.
  • The noise is rhythmic and sees to happen once per wheel revolution - or very least its frequency depends on the wheel rotation speed.
  • It doesn't seem to depend on pedalling - whether I pedal slowly or fast, frequency of squeaks seems to only depend on the actual wheel rotation.
  • When I stop pedalling completely, the noise doesn't disappear or become less prominent - so I haven't checked the bottom bracket and drivetrain yet apart making sure there is nothing obviously wrong with them.
  • It is not brake pads or anything else rubbing against a rim - the wheel is reasonably true, and disabling the V-brake completely by undoing the cable doesn't affect the noise.
  • If it makes a difference, it's a folding bike with 20" wheels (Dahon Vitesse).
  • As it is a folding bike, I check the frame lock and lubricated it, and it didn't help as well.
  • Steering doesn't seem to affect the noise volume.
  • It is not the seatpost or saddle (checked that carefully because the noise is only present when I am riding the bike).

What should I check first now? Abandon the idea that it's the front of the bike that is squeaking and check the rear wheel and/or bottom bracket bearings? Check the handlepost (it is new as it has been replaced this winter)? Nuke it from the orbit?

  • Do you use disk or rim brakes? Brakes are often a cause, the disk may be warped or the wheel out of true. – Carel Jun 15 at 14:36
  • Rim brakes (V-brakes), but like I mentioned, when I disengage the brakes so the pads are a good inch away from the rim it doesn't solve the problem. – Yuriy Jun 15 at 15:48
  • Without sounding daft here, have you checked that its not tyre rub? This can often only occur under load (i.e. weight on the bike)? Does the volume change at all? If so when? – Henry Jun 15 at 19:04
  • Will double check, thanks, but it's a new Schwalbe Marathon tyre, pumped to an appropriate pressure, so don't think it's likely. Will post if this turns out to be the case though. – Yuriy Jun 15 at 19:06
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    Remove the wheel, remove the tyre and tube, and then put it all back together. Make sure to check the tyre is mounted on the bead correctly etc after inflation - see if this changes anything. – Henry Jun 15 at 19:28
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Disclaimer: squeaky bike are non-linear, non-obvious phenomena.

Although it happens in sync with wheels revolution, you noticed it happens with load on the bike.

I guess it is one manifestation of resonance (as known in physics). For example, some bike will start vibrating when rode handless at a certain speed (i.e. 20 km/h) that it is impossible to keep on riding them handless. But if you ride them with your hands on the handlebar, past the critical speed, you can ride them handless at hiher speed (for example 25 km/h).

So all your consideration on the origin of the noise are most likely wrong. There is some periodic, elastic wave propagating through the frame and its components, an elastic wave which is expressed as a squeaky noise. What is the source of this elastic wave? probably some very small mis-alignment of one of the wheels.

Maybe it is the latching mechanism, but lubing it is not helping because you would need some grease in addition to the tightening of some screws (check

). Maybe it is the seat post, enhancing the resonance (did you try with much higher/lower seatpost?). Maybe it is the ratchet system in the cassette.

I would try to swap your wheels for similar wheels (both, then only rear and then only the front one). Ideally I would play with the spokes'tension.

Does the problem happen when someone much lighter/heavier than you ride the bike?

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  • Thank you, I also came to conclusion it's a spoke, one of which is too loose. When I hold the wheel at 9 and 3 o'clock and try to twist it, there is squeaking similar to what I hear when cycling. Tightening the spoke doesn't help though, it seems like there is a problem with thread so I need to find another mechanic (don't want to take it back to the one who misdiagnosed the problem). – Yuriy Jun 17 at 20:38
  • @Yuriy If you use the bike for commuting, I would suggest go big and buy a front wheel with a hub-dynamo: the best money you can spend, plus it should solve the squeaking issue :) It may seem an overkill, given the issue is "just" a spoke ... but taking into account all the time you spent on this issue, a new wheel will be just a minor additional cost. – EarlGrey Jun 18 at 9:32

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