chain jumping off jockey wheel
Hi
Can someone give me some advice please. My chain is jumping off the lower jockey wheel when I change down to a small sprocket. I've tried a new chain that I measured as advised by the Park website and I've even replaced the jockey wheels but I'm still getting the same problem albeit not as often.
The mech is an old (7speed) shimano 105 and probably only done about 3000 miles.
I'd be grateful for any ideas on why its doing this as its driving me insane!
Thanks
Can someone give me some advice please. My chain is jumping off the lower jockey wheel when I change down to a small sprocket. I've tried a new chain that I measured as advised by the Park website and I've even replaced the jockey wheels but I'm still getting the same problem albeit not as often.
The mech is an old (7speed) shimano 105 and probably only done about 3000 miles.
I'd be grateful for any ideas on why its doing this as its driving me insane!
Thanks
0
Comments
-
Chain might be too long ?0
-
could the rear mech cage be twisted? has it received a knock that might have left it out of line - that might explain the chain unshipping.0
-
This happened to me recently.
I needed to adjust H and L limit screws and it seems fine now.
The mech is quite old too (4 years) so it has a slight bend to it - which I'm sure helped contribute to the problem.0 -
Also check frame gear hanger alignment - more likely to be bent than the mech itself - is the jockey wheel cage vertical and parallel with the front-rear axis of the frame? Your LBS will have a tool to check and adjust alignment - trying to bend the frame yourself can result in a bust hanger or even a broken frame.Make mine an Italian, with Campagnolo on the side..0
