Hello, This is my first post and my first endeavor of this sort, so thanks in advance for any patience required:
I have a 2004 Specialized Stumpjumper FSR Expert Disc. When I am on the bike the frame seems to flex and cause the rear disc brake to rub. If I start out with the caliper centered on the rotor, it moves too far to the side and rubs terribly.
The only way I have been able to overcome this is to start with the rotor rubbing on the opposite side, and hope that it comes back to the center when I am on the bike. It is truly "hit and miss."
My LBS has been unable to figure out a solution, and they say that Specialized has never heard of this problem. Has anyone else encountered this and come up with a solution?
.... When I am on the bike the frame seems to flex and cause the rear disc brake to rub. If I start out with the caliper centered on the rotor, it moves too far to the side and rubs terribly.
Are you sure that it's the frame that's moving and not the wheel?
I have a 2004 Specialized Stumpjumper FSR Expert Disc. When I am on the bike the frame seems to flex and cause the rear disc brake to rub. If I start out with the caliper centered on the rotor, it moves too far to the side and rubs terribly.
Thanx.
This happens all the time, but I doubt it is the frame.
It could be
The caliper pistons retracting unevenly, or not at all. This can vary throughout the course of a single ride. Welcome to disc brakes.
The quick release changing the centering of the rotor when you tighten it.
A bent rotor
The rotor has not been mounted correctly on the hub
The caliper needs to be shimmed so that the rotor is centered directly within it.
The wheel spoke tension is WAY out (unlikely)
Try eliminating these from your list of potential problems before you blame the frame. Some of these factors can come and go. Also, don't be afraid to change bike shops for some different advice. Ask around and find out who knos their stuff.
