Fsa transmission creak

Steve I

I've had FSA Gossamer Mega EX0 cranks and bb cups on my bike since new (2 years). They've ran perfectly until recently when they've started making the most horrible creaking and clicking. These FSA cranks are similar in design to Shimano Hollowtech 2 i.e. the left crank is removable, and has 2 opposing pinch bolts. The axle is permanently fixed to the right crank.

The creaking and clicking only occurs on the left crank power stroke. Single leg pedalling on the right crank does not produce any noise at all. I'm virtually certain it's coming from the bottom bracket area. It's not the saddle as it occurs standing or seated. I've eliminated the pedals and cleats, and the chainring bolts are tight. If I hold the brakes on and lean against something I can get the left crank to creak and click while stationary.

I've removed, greased and retightened the left crank a few times with no success. Anyone got any ideas as it's driving me nuts. Ironically I've got another bike with Tiagra Hollowtech 2 cranks and that has the same problem only not as bad. I'm beginning to think that external bearings are a poor design.

karlmoreton

Remove and regrease the bottom bracket cup threads, make sure thread in frame is grit free and clean before refitting and grease pedal spindle threads and reassemble.

Also worth checking the headset crown race is dry and well greased as this can give similar symptoms.

And finally I have had experiences of a worn chain causing the creaking.

Hope that helps.

Steve I

Thanks for that, I'll try removing and re-greasing the bottom bracket cups as the next step. if that fails it looks like a return to a square taper crankset for me - or earplugs.

John.T

Check the bearings while you have them off.

topdude

Don't discount the seatpost as a possible source of the creaking, it can still creak as the frame flexes, same goes for the wheels / dropouts, bars / stem.

John.T

The hub Q/Rs can also be the cause of strange creaks. Try greasing them.

onbike 1939

FSA outboard bearings on this chainset have a reputation for needing replacement due to wear around 2000 miles. They can be substituted for Shimnao 105 outboard hubs which don't have this problem.

Steve I

Thanks very much for all the replies. Onbike, that's interesting, I've done about 5000 miles on this crankset. I'm more of a Tiagra price person, are they interchangeable with 105 cups, cheers.