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I've got an annoying creak, and I've been through everything I can think of to track it down - I'm hoping I've missed something.

This is on my Canondale Topstone road/gravel bike. It's an alloy frame with an FSA Omega screw-in BB and self-extracting cranks, otherwise a 105 drivetrain.

On every right pedal stroke, there's a creak, if there's any force at all. It's not detectable on the stand, whether or not there's a chain installed (maybe a hint if I try to hold the brake on to give some resistance?), and it's not detectable if I pedal while the bike descending fast enough that I'm spinning the pedals but the bike is really freewheeling. The volume seems pretty constant, except that it's louder in the big ring. In the little ring there's a hint of it on the left stroke as well. The pedal position seems consistent at the top of the downstroke, say around 1 o'clock. It's hard to hear except in quite conditions, and on the very smoothest of surfaces (i.e. rarely) I think I can feel it through the pedals.

  • I've changed the BB. On checking, one of the cartridge bearings was loose - not in the race but between the race and the crank, so I replaced the whole BB. It's not loose any more. I thought this fixed it back in March but my test ride must have been too noisy - either that or it went away for days; either way I've checked the cranks and BB again recently - no play.

  • It's exactly the same when I get out of the saddle (I had a saddle-bolt related creak on the same bike).

  • Swapping pedals and wheels didn't stop it (I run M520s for road, but put some M424s on for a gravel ride, along with my gravel wheelset.

  • Pedalling with just my left foot makes it go away. Pedalling with just my right foot is inconsistent but that's probably me.

  • I could almost believe it was from frame flex, but it's present even at low seated efforts. The mainly one-sided nature doesn't really fit with that either.

  • The crank isn't clipping anything as the pedals goes round, and pedalling while looking down, the chain is behaving normally.

  • It makes no difference whether the rear through-axle is normal tight or super-tight, and cleaning the axle seats doesn't help either.

  • It's not getting (much) worse - I must have done at least 1700km since I first noticed it (and got through a whole chain - the first time I tried to find it was a service in March and I've just had to replace the chain again).

At least the last point hopefully means it's not a sign of impending failure, but it's getting annoying, especially as I'm usually pretty good at catching this sort of thing - though of course not being able to replicate on the stand doesn't help. So what have I missed?

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  • 2
    Have you inspected the down tube for cracks? That's the kind of creak I had on my Trek when the frame cracked.
    – DavidW
    Commented Jul 9 at 13:46
  • 3
    It reminds me something that took me a while to solve: a loose bottle cage bolt.
    – Rеnаud
    Commented Jul 9 at 13:55
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    @DavidW a major reason for buying a gravel bike as my endurance road bike was to get something a bit more robust than a light road bike, hopefully avoiding that kind of issue (see also my steel tourer that served the same duty). I'll have a look this evening
    – Chris H
    Commented Jul 9 at 14:10
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    The times I'v had such a symptom it was 1) A cracked plastic BB Counter-screw (I don't know its real name but I mean the other piece you screw on when installing a sealed bottom bracket) and 2) a loose chainring bolt.
    – Jahaziel
    Commented Jul 9 at 14:34
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    @Criggie no rollers or assistant, though I do have a very basic trainer somewhere (I've never used it). I think, balancing briefly rather than trackstanding, that it does creak, but only once - backpedalling then pushing forwards again doesn't, but of course relies on letting the bike move. I haven't been able to find a spot that causes a repeatable creak without the bike moving forwards.
    – Chris H
    Commented Jul 10 at 6:15

3 Answers 3

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It's likely failure of the permanent joint between the DS crank and the spindle.

To corroborate, take the cranks off, take the pedals off, and see if you can get that joint to make the noise or a sensation of movement when bare. One way is put a piece of wood down and push the tip of the spindle against it hard in various angles, holding the crank by the pedal eye area. (Here the spindle is steel and so hurting the spline or bearing contact areas by accident if using modest care and a wood contact surface isn't a huge concern. If it were aluminum you'd need more caution). You could also put the left crank back on with it out of the bike and reef on it in various positions that way.

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  • That makes a lot of sense, even down to the bigger ring being louder - it's got more leverage. I'll have to find a chance to strip it down.
    – Chris H
    Commented Jul 9 at 17:31
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    Heads up to anyone reading this: some Shimano R9100 and R8000 cranks are prone to delamination and should produce similar symptoms. This can occur on either or both arms, though.
    – Weiwen Ng
    Commented Jul 9 at 17:36
  • @WeiwenNg to complement your comment, it looks Shimano has even a replacement programme for that: bike.shimano.com/en-EU/information/customer-services/…
    – Rеnаud
    Commented Jul 9 at 19:28
  • I couldn't make it do anything off the bike, but I wonder if I should have reassembled, fixed the left crank in a vice (with wooden blocks) and leant on the right crank. As my chainrings are pretty worn, I've ordered a whole new crankset. That will be a good test. It's a shame in a way, because if I hadn't just replaced the BB I'd review that whole part of the drivetrain - the 19mm hollow axle limits my choice of swaps. On the plus side I'll have a spare crankset to play with changing ratios.
    – Chris H
    Commented Jul 14 at 13:07
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I had a similar experience which I eventually tracked down to slightly worn rear cassette teeth in my most used gears, which allowed the chain to "creep" slightly up the teeth under load, resulting in a creaking sound. Prior to replacing my cassette, the creak had persisted through all the following troubleshooting:

  1. rebuilt BB30
  2. cleaned and retorqued spider and BB bolts
  3. replaced chain (despite no evident chain-stretch)
  4. replaced 1x chainring
  5. swapped pedals off another bike
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  • I've got a new cassette on the way, because even the one from the less-used wheelset slips on a new chain on a few sprockets. I would have said that swapping wheels tested for that, but with the last chain only lasting 1700km I must have been testing on more worn parts than I realised
    – Chris H
    Commented Jul 10 at 6:19
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All I can tell you is where I would start. Disassemble your BB. Remove your cranks from the spindle and then the bb cups from your frame. Use your choice of non-hardening Loctite or Permatex #2 (also non hardening) on your bb cup threads. before assembling, use your Vernier caliper to check if your bb shell is ovalized. All it takes is a couple of mm to cause a creak. Permatex will stop the sound if this is it, but it's not fixed. Re assemble using a very light smear of grease on the spindle flats (or splines if that is what you have) and use the correct torque on the crank arm bolts. Use loctite or permatex on your pedal threads when you tighten them. Still have a creak? It's not the BB if you do after this.

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