Originally Posted by
greyghost_6
I don't think you have done anything wrong. If nothing else is rubbing you have done a great job. What you are experiencing is what is called being "cross chained" you have your chain going from your smallest gear in the front to the smallest gear in the back causing the chain to look like \ when looking down on it. You want to make it look like | and be straight. That gear ratio is not normal to be in. The rider should shift into the middle ring before depleting all the higher gears in back. Im not sure what joseph and operator are saying but if im reading you correctly it seems you are in good shape.
I know i typically wouldn't ride in that combo of 39/12, but I am getting rub on the last 3 small cogs of my cassette so i know something is up. I feel like i should be able to get it set up so there is no rub at all in any gear combo because thats how it was operating before I had to replace it. Of course that was set up by the mechanic at the shop!
I really want to get this so i don't have to rely on a shop like i always have in the past.