cranks/bottom bracket noise

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Anonymous's picture

Hi, this is my first time posting a thread. Went riding yesterday and started hearing a horrible squeak/crack/pop sound coming from the cranks/bottom bracket. Have talked to 2 bike shops on the phone--first one said noise could have resulted from riding in the rain and needs to be cleaned out; second guy said will require a complete overhaul. Anyone with experience on this??

thanks in advance!

Anonymous's picture
Chaim Caron (not verified)
Same problem

"I'm having the same problem: a creaking sound that seems to be related to the rotation of the crank. Sometimes it sounds like a wet sneaker squishing and sometimes it sounds like a little mouse: ""eeek"".

I think this can be caused by various things and is hard to diagnose. One person suggested it could come from the free wheels in the back of the bike, and that the sound is transmitted down the frame and so it seems to come from the front. How old is your bike? Mine is about 1500 miles old and my bike shop said it's unlikely that the bottom bracket is worn. This one will probably be hard to track down, but please keep us posted if you find the solution. My advice would be to find a good bike shop and ask them and expect to pay some money for the repair. Two bike shops I can recommend: Sid's at 34th and 2nd and Bicycle Habitat on Lafeyette south of Houston. There was another thread recently on high quality bike shops in the City. Good luck!
PS I tend to doubt that this will require a complete overhaul. I'd be suspicious of that suggestion."

Anonymous's picture
Bill Vojtech (not verified)
It could be...

Some bikes are more prone to this than others. I've noticed that many Cannondales have noisy bottom brackets. I've heard many people say that they tried having it worked on to no avail. They just live with it. I don't like that way, since their noise disturbs me.

If the left and right sides of the bottom bracket are not milled parallel it can cause a bad fit with the bottom bracket cups and a squeek could result.

It could also be the crank bolts are loose. This can destroy the crank arms if you keep riding with the squeek.

It could also be that the pedal is not screwed into the crank properly or there is something wrong with the pedal bearings or your cleat might have some gravel or sand embedded in it.

Clean the cleats and pedals. If you know how, and have the right tools, tighten the crank arm bolts and make sure the pedals are screwed in properly.

Check the bottom bracket axel for sideplay/binding, (slip the chain off the chain rings). There should be no or minimal sideplay and the axel should spin freely.

Check to see if the fixed cup, (right), is seated against the bottom bracket shell and that the lockring on the left cup is tight.

If everything checks out and it still squeeks, you may have to have a good shop look at it. They may have to take apart the bottom bracket assembly and reface the bottom bracket shell. I'd only have a good shop do this since it can't be un-done and if it's not done right you might need a new frame.

Anonymous's picture
"Chainwheel" (not verified)
Troubleshooting a Squeak

"Squeaks can often be hard to isolate. If the squeak/pop occurs in synch with each pedal revolution, it probably involves either the pedals, cranks, or bottom bracket.

First, grab each crank arm and push them sideways to see if there is any play. Second, lift the chain off the front rings, and turn the cranks. They should turn smoothly and quietly. If not, the problem is in the BB. Finally, make sure the squeak isn't coming from your shoes or cleats.

Sometimes the cause of noises / squeaks can be far removed from the apparent source. They could be related to the chain, cassette, or even the saddle rails. A liitle grease can do wonders once you find the source!

How old is the bike. How many miles on the chain?


Anonymous's picture
Anthony Poole (not verified)
Could be pedals and cleats

It's definitely worth checking the pedals and cleats, assuming you ride with such things. Try riding with just one foot on one side, then check with the other foot on the other side to see if the noise is only on one side. If it is, the chances are the pedals/cleats may have something to do with it, although the noise you describe sounds more like the bottom bracket.

I would suggest the same to Chaim, as the noises he describes sound very similar to noises I have occassionally experienced with Look cleats, especially if you bike only has 1,500 miles on the clock. It shouldn't be the freewheel, with such a low mileage. If it is, you might want to question the shop where the bike was built, unless you bought exceptionally poor quality components.

Anonymous's picture
Christian Edstrom (not verified)

Try to isolate the squeak one step at a time. It could in fact be the bottom bracket or crank bolts, but I would start by checking the chainring bolts, which I've found usually work themselves slightly loose over the first 1000 miles on a new bike.

I'd tighten the chainring bolts (5mm allen) and ride around. Then I'd tighten the crank bolts (6mm allen or 8mm allen).

If the noise still appears, then I'd have a look at the bb. Of course, if it's a cartridge type, no chance to clean or overhaul. Just replace. But that seems unlikely, given the low miles.

- Christian

Anonymous's picture
Yung (not verified)
problem fixed

cool--thanks for all the replies. took my bike to Bicycle Habitat, turned out just needed to tighten the bottom bracket and cranks--the bearings and seal was fine--$10 dollar job, deal!
first thing noticed was the play on the pedals, but was obvious this was not responsible for the entire problem. there wasn't any play on the bottom bracket so it was just a matter of tightening a few things. i've had my bike for 3 years and this is the first time i've paid any attention to the bottom bracket area.
thanks for all the above info--will be helpful for the future--

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