Hi All,

I did a search through the threads here and didn't find any that sounded like my situation.

I've been commuting on a Trek 7300 for a few weeks. Lately (last week or two), it has become increasingly difficult for the chain to "catch" when moving up to the big ring on the front. As far as I can tell, the derailleur is adjusted properly, in that it moves the proper distance away from the frame and the chain makes a lot of noise rubbing against it and the chain ring, but it doesn't seem to grab.

Sometimes, I can make it grab by pedaling backwards a bit and then forwards. Other times I can get it to go by changing gears in the rear while trying to get it to shift in the front. Still other times, it shifts perfectly fine.

Any ideas? Do I need to raise up the derailleur? I've tried adjusting the limit screws, but of course it always shifts right on the bench.