Originally Posted by
loimpact
Thanks FB. I'd have replied sooner but am having some image hosting issues. (Damn Skypath) I've measured gear to dropout gap @ .108" (approx 2.74mm) and took some pics at different angles if you have an opinion on what you see......
It's hard to see, but the gap seems to be much more than the .108 you're measuring. Eyeballing the chain for a reference, the gap would appear to be closer to 8mm than 3mm. In any case, if the gap were LT 7mm or so the 8mm chain couldn't jam itself in there.
Measure again, or if you wish, shift the chain to high, and shoot straight on so we can see the clearance between the chain and dropout (should be 1mm or so) and if it's 4-5mm that's your problem.
As I said earlier, it's normally physically impossible for a chain to jam itself between the sprocket and dropout, though (rarely) chains can get jammed under a seatstay where it meets the dropout.
BTW- can't tell for sure, but there seems to be an inside shoulder on the dropout, which may be a factor. But the dimensions I'm referencing are at the height of the chain (check all the way around), not the axle.