I recently (2 days ago) had a K-Force Carbon Megaexo crankset installed. The mechanic was well aware of the facing issue with these cranks and all seemed to go quite good for the first ride - 70Km. Today though I noticed a scraping sound coming out of the BB after about 30Km into a 60Km ride. At first it was just the occaisional scrape. It progressively got worse throughout the ride to the point where it would make the sound for about 1 minute of pedalling then silent for about a minute then back on again and so on.....
Is this an issue that anyone else has come across and what if you have did you do to fix it?
It sounds like the crank loosened up. Take it back to the guy that installed it right away.
It is one of two things: He missed something when putting it together. OR The crank loosened up which sometimes happens witha new crank set.
Thanks for the quick response.
It's definately in the BB. I just dropped the chain and gave it a spin. It seems kind of tight through the whole cycle. I guess this is normal for new bearings? The sound is very high pitched almost like there is glass in the bottom bracket. Does that make any difference to your suggestion?
Thru the interweb it is hard to say what the problem is.
The outboard(and ISIS/Octalink) bearings have more drag than cup and ball bearings but they should still be pretty quiet.
So I still have to say, "Take it to the shop" or another shop or even a freind that knows what they are doing.