Originally Posted by majohnst
Thanks for all the advice. I tried a few things and here is what I found. I lubed the chain, but that really didn't help any. The problem only happens when the chain is in the larger cogs on the rear cassette. I have a triple, and the gear jump problem only happens on the 52 and 42 front cogs. So I am assuming it has something to do with the angle of the chain. Right before the jump happens, the front cog doesn't catch the chain correctly and snags. This causes the rear hanger to move forward. On a side note, the bottom of my hanger seems to be tilted slightly towards the wheel, so it is not perfectly vertical. Would that be apart of the problem?
Yes it is. And you should get it fixed. Take it to a shop and ask them to do it or ask them for advice on how you can do it (there are ways but I'm tired of getting my chops busted today). If it is a steel hanger, it can be bent back without problem. If it's aluminum you might need a new hanger, if your bike has replacable ones. Get it fixed, your bike will thank you.
Stuart Black