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I am in an ongoing battle to try to get a squeak to go away. Here is what I know (sorry for the length):

1) The sound is a very loud squeaking (chalk on the board) that, at its worst, persists throughout the entire revolution of the crank. It seems to be coming from the crank/chainring/BB area, but I would not bet my life on it.

2) I think that it is likely from that area, because its periodicity seems to be linked to the crank speed, not the rear wheel speed (i.e. it sounds the same for all gears in the back, there is only one front chainring).

3) I cannot replicate this sound when the bike is in a stand, it needs to have some (not much at all) resistance.

4) I have tried pedaling with one leg at a time (hard with flat pedals) and it seems to occur for both sides.

5) When it gets really bad, nothing with shut it up while riding. But, when it is just starting to make noise, back pedaling several revolutions will quiet it down for a minute or so.

6) It seems to be quieter in the morning than evening. Could just be my imagination, or temperature differences.

7) The sound totally goes away when I clean and lubricate the chain, only to return about 15 minutes into the next ride.

8) Fed up, I replaces the chain, cassette, and chainring a couple weeks ago, but the sound persisted.

9) It shifts great.

So, I have a hard time believing that it is the pedals or bottom bracket given point 7. I thought it may be some weird compatibility with the chain and chainring, but it shouldn't be. I currently have a Nashbar 9 speed chain and a Vuelta 42t chainring (says it is compatible with 7-10 speeds). The old setup with the same noise was a Shimano 9 speed chain with Surly fixed gear chainring. The rear derailleur is 4-5 years old. I thought that there could be some issue with chain tensioning, but I can't really see that either.

I think I've provided everything that I know about it, but let me know if anything was too vague. Thanks.

  • This is very hard to read -- please reformat it. – Batman Jul 21 '15 at 12:52
  • Don't know if this is you but I had squeak that thought was drive train that turn out to be headset. – paparazzo Jul 21 '15 at 13:11
  • I feel like it has to be the chain or something touching the chain, given that lubing it fixes the problem for 15-20 minutes. – algs Jul 21 '15 at 13:15
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    #3 together with #7 don't make much sense to me. #3 suggests BB related problem but #7 suggests chain friction somewhere (to the chainring? to the chainstays?) but still you mention that it's the same for all gears in #2 (so chainstay rub is out)... Place the bike on the stand and inspect whether the chain comes very close to anywhere that it shouldn't. Also, remove the chain and stand on the bike, trying to pedal. Hop on the bike hard. Is the sound there? – cherouvim Jul 21 '15 at 13:20
  • It is befuddling. I am usually fairly competent with bicycle maintenance, but I really have no idea here. I have not jumped around on it without a chain on. I'll give it a shot tonight. There is not a whole lot of places the chain could rub. The only thing up front is the single chainring. I'll look closer to see if anything seems like it could rub in the back. – algs Jul 21 '15 at 13:30
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One thing you haven't mentioned: when does the noise occur relative to crank position? Does it make the noise through the entire revolution of the crank arm? Is the noise loudest at a certain point in the crank revolution (say 2 o'clock)? I had a customer come in one time with a sound they absolutely could not get rid of and they went through most of the steps you mentioned. Turned out is was one of the chainring bolts. A little grease on the threads and the problem was gone. It was a ridiculously easy fix for a ridiculously maddening problem!! May not fix your problem but it only takes a couple of minutes to try this solution. You should make sure that all threaded surfaces have grease or anti-seize compound on them. Bare metal threading into bare metal is no-no as it leads to annoying noises, bolts coming loose or bolts seizing/corroding. Good luck!

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Get over it HAS to be the chain. That could be a coincidence or a procedural side effect. Are you dripping oil on a loose chain ring. Oil spills onto a derailleur. Crank could be rubbing against the frame and the oil spills onto that. Do you ride a certain route or a certain way after a lube. You replaced the chain it did not fix it - you also have evidence it is not the chain. You state the sound seems to come from the crank.

Go after anything that can squeak. Rather than dismiss what you think it is not eliminate anything it could me. Lube and adjust everything. What is the harm? You just dismissed the headset - what is the harm in pulling the headset and lube and adjust. Pull the seat post and lube and torque to spec. Same with handlebars. You don't need to replace the bottom bracket but pull it and spin the bearings. You state this has been an ongoing battle and you are fairly competent mechanic. Do an end to end maintenance on the bike. What is the harm?

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    May as well rewrap the handle bars while I'm at it. No harm there. I did not say it HAS to be the chain. I said that I THINK it has to be the chain or something touching the chain. I've addressed most of the drivetrain ideas you have mentioned. I have not pulled the bottom bracket, nor have I replaced the rear derailleur. I have had phantom creaks be attributed to seatposts before, and I really don't think this is it due to the screeching sound (I know, what's the harm?). Sincerely, thanks for your input. – algs Jul 21 '15 at 19:13
  • OH, and cork tape squeak less. – paparazzo Jul 21 '15 at 19:20
  • Cloth tape with shellac! Totally silent. Also a few ounces lighter than cork so it will save critical seconds off that big climb. ;) – ChrisL Jul 21 '15 at 20:24

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