My chain falls off when I pedal backwards



nevermind

New Member
Mar 7, 2004
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when it's on the big rings. It's a 2001 Stumpjumper comp fsr. I think it might be bad alignment. Is there a fix? If not does anyone have a rear end for sale?
 
Originally posted by nevermind
when it's on the big rings. It's a 2001 Stumpjumper comp fsr. I think it might be bad alignment. Is there a fix? If not does anyone have a rear end for sale?

Could be the rear derailer needs adjustment and/or is need of alignment.
Check Park Tool site at:
http://www.parktool.com/repair_help/FAQrindx.shtml
Also look at your chain when back pedaling to see if there is a stiff link.
Is the chain parallel with the top tube when you are in the middle- middle?
Is the chain proper length?
When did this start happening?
 
Originally posted by nevermind
when it's on the big rings. It's a 2001 Stumpjumper comp fsr. I think it might be bad alignment. Is there a fix? If not does anyone have a rear end for sale?

Forgot to ask if it falls off the front or rear.
If it's the front, look for a bent chain ring.
 
The chain will usually fall off or try to drop to smaller sprockets if you pedal backwards on the largest rings because it is stretched from its neutral position. Don't pedal backwards.
 
Originally posted by Hecubus
The chain will usually fall off or try to drop to smaller sprockets if you pedal backwards on the largest rings because it is stretched from its neutral position. Don't pedal backwards.

Thanks. Your point is well taken but my old Stumpjumper never did this.
 
Originally posted by nevermind
Thanks. Your point is well taken but my old Stumpjumper never did this.

Many things can cause this. There could be a difference in the front and rear chainrings that makes it more apparent in one bike than the other or a simple difference of chainlength. Most likely the freehub is tighter on your new bike than the other older one. This will cause the chain to go limp when pushing it back causing it to move around. Its still rather normal anyway. Most bike will do the same.