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clunk in drivetrain

klutch

Monkey
Jan 25, 2007
144
0
dirty jersey
I got a Specialized Hardrock Pro nothing stock but the frame.Last year I changed the cranks and bb, cranks are Race Face Evolve DH and the bb is RF XC 68/113. I changed them because of this clunk in the rotation of the crank in the same spot all the time and now it's back again. I also have a new chain, front and rear deraileurs, pedals, rims and hubs. My ques. is is this clunk likely the bb again? I've heard some crappy stuff about the RF bb, any suggestions? I just purchased a new Giant XTC frame and am swapping alot of the hardrock parts and don't want the same probs. Any help is appreciated, thanx
 

speedbump

Chimp
Mar 27, 2003
82
0
Methow Valley, WA
It's possible that your bottom bracket is just loose in the frame. When the cups (or cartridge) loosens slightly, it will rock slightly under load and create a clunk you can hear and feel. Of course, it could be a bearing dying as well.:confused:
 

Avy Rider

Monkey
Feb 26, 2003
287
0
Muskoka,Canada
This may be an obvious question but are you sure that your crank arm isn't hitting the chain stay? Sounds silly but sometimes it's the obvious that can elude us.
 

_*sTiTcHeS*_

Monkey
Apr 24, 2006
386
0
new chain should have fixed that though. maybey if you swap out your parts with someone else for like a day, one by one, you can pin point the problem. for instance, swap a crank arm or a pedal with someone and see if they notice the problem and if its gone on your bike.
 

klutch

Monkey
Jan 25, 2007
144
0
dirty jersey
I said fvck it and took it out,but in reality I was building another bike but it moved more than 1/8 of an inch I've never seen one this bad.I sent it back to greenfish so they can warranty it for me with race face and in the mean time and for ever I put a Truvative Gigapipe in there and it's nice it even pedals easier with the 34t ring that I put on I had a 32t on with the rf bb,so now I'm smooth and fast women beware!