So I've been building up a late 80's steel frame to a modern 11 speed, but still using downtube friction shifters. After doing a few runs up and down my street all felt OK so I decided to take it out on it's maiden voyage.
A couple of miles down the road however something didn't feel right, after pulling in to a cul de sac to try and see what was wrong I was testing going up and down the gears a few times when the pedals jammed. Luckily I was going quite slow and managed to jump off. Anyway it appears one of the jockey wheels became jammed between the spokes. I'm guessing I may have offset the H limit screw too far or something?
Anyway the damage is it's cracked the housing of the rear derailleur hanging bolt (see below). Is this safe to use or should I get a new one?