You don't need to be an 'investor' to invest in Singletrack: 6 days left: 95% of target - Find out more
I may be about to ask a spectacularly stupid question, but here goes...
The bike is 2x11 105, R7000 I think. On my last ride, at the foot of the last hill something* occurred and the chain snapped, rear mech hanger snapped and the front mech wedged itself in the chainrings.
I've replaced the mech hanger, but it looks like the rear mech itself is bent, as the top and bottom jockey wheels aren't in the same plane. So viewed from the rear, or from the bottom, the top jockey wheel lines up with the sprocket, and the bottom jockey wheel is then angled out from that.
My stupid question is: in an unbent mech the top and bottom jockey wheel should be both in line with the sprocket, right??
So far it seems to work (in the workshop), but I never looked that closely at it before it broke, so I'm not sure whether to try to bend it back into shape, replace it or leave it as is.
* my best guess is the band for the front mech shifted, so the mech itself got stuck on the chainring teeth. That yanked the rear mech taut, breaking the mech hanger, and the chain then snapped. Fortunately I wasn't going fast, so was able to stop fairly easily.
Sounds very much like it's bent, personally, i'd replace it (we have very little luck straightening bent mechs, and there's a possibility it may also let go in the near future), but if it's working and your happy it's not going to damage anything else,why not just use it.
Have you checked the new hanger with a tool ?
Just because it’s new does not mean it’s aligned on your frame properly.
But if the indexing is fine then hanger is probably ok
The two jockey wheels are not in alignment.