This one is a mystery to me. I ride a carbon road bike and just recently a clicking noise has developed when I push hard on the left side crank only (right side makes no noise). I have tried different pedals and the result is always the same. I replaced the BB, no change. I have removed, cleaned, regreased all the moving parts. Any suggestions?
-
2Not a duplicate, but we've got a similar recent question at bicycles.stackexchange.com/questions/80694/… with a lot of similar characteristics. Try reading through the comments, suggestions, and answers to see how they apply to your situation.– Criggie ♦Sep 9, 2021 at 0:31
-
Are you using cleats? Have you tried different shoes?– CarelSep 9, 2021 at 7:12
-
Have you tried removing and re-seating the crank itself (on one bike this alone helped when it started on warmer temperatures)? Is the BB axle with both cranks removed cleanly spinning (no grinding, smoothly spinning, no radial/axial play)?– try-catch-finallySep 12, 2021 at 9:22
2 Answers
A lot of carbon-fiber frames with press-fit bottom brackets have a problem with bottom-bracket creak. This is because press-fit bearings depend on the bearing cups being perfectly parallel and in line, and the frames are fabricated with the bearing cups out of spec.
There are replacement bottom brackets that come with their own sleeves that thread together in the center, which force the bearings into alignment.
It's odd that this would result in one-sided clicking, so this might not explain it.
I just repaired this kind of left-sided click on my bike. The left pedal outer bearing was dead even if not that old. There was no sand inside or anything like that, but the bearing is really grinding even in my fingers and the click is gone with a new piece.
Of course, your case might be different.