HUBbers opinions please

[mapep]

just bought a new Felt F75, great ride except when in the biggest gear (big chainring,smallest cog) there is a hell of a vibration from the components which is transfered to the pedals. Tried many alternatives;different cassette, dura-ace ultra slim chain,derailer adjustments but to no avail! It's going back to the agents next week but would appreciate your thoughts / opinions / suggestions. cheers. Mapep

 

hey HUBbers,the problem was the bb was not perfectly aligned,perhaps thread on crank bearing or crank itself, makes sense because as the chain moves further away from a true alignment ie: large chainring & smallest cog, the error would be at its worst, or something like that ! thanks for your comments

mapep2008-11-27 12:57:36

[buckstopper]

The vibration may be coming from a too long chain, and emanates from the rear derailleur. Put the bike on a stand and turn the pedals in the gear you mention. The derailleur does not have enough tension and the chain rubs on parts it shouldn't. Generally while a well tuned bike should run on the extreme gears (53-23 and 39-12) it's not the best habit from a drivetrain lifespan perspective

[mapep]

hey buckstopper,thanks for the reply,I'll keep u posted what the agents have to say

[lex123]

i think that it could be sand between the bottom bracket bearings and the crank arm, or the bottom bracket bearings could be worn, or full of sand.

[Speed Devil]

When in the smallest cog at the back check if the chain is catching on the lockring. Not all lockrings are the same diameter.