Hiya,

I have just got a nice second hand Felt F85. It's practically brand new and seems like a great bike. I am new to road riding and have a quick question.

When shifting from the big ring to little ring on the front, sometimes, especially if I am in a high gear on the rear, the chain does not click properly into the teeth, and grinds horribly on the chainring. It has only done it twice but already caused a bit of wear that I'm really annoyed about...

Sheldon Brown mentions, "you should never use small-small combinations anyway". Is this the problem, should I just not be using small-small at all? Why is this? Even so the chain should surely not be grinding on the chainring! How can I stop it?

Thanks.

small to small, and large to large, are both cross chaining. Any extreem angle of the chain is cross chaining. This will cause premature wear on the chain and chain rings, leading to early replacement.
If your front derailure is rubbing in cross chained situations, then thats why its rubbing, you are cross chained. if it rubs in other gear combinations then it needs to be adjusted. Or you need to learn how to trim the front derailure.

If you are in the small ring in the front. then the last 2 or 3 smallest cogs on the cassette in the rear would be cross chaining. If you are on the large ring in the front. Then the first 2 or 3 larger cogs in the rear would be cross chaining.

Trimming the front derailure means to move it a small amount to keep it from rubbing when the chain angle becomes enough to cause it to rub. Most modern shifting, on the front derailure, have a position in between each gear for this purpose. there will be a minor click in between the major click that signifies a complete gear shift. This minor click is the gear adjustment or trim position.

cross-chaining will wear your parts faster, but your chain should not *grind* in any gear.

check out this video: https://www.youtube.com/watch?v=38vdA5OOBxI
it's for SRAM FDs, but it's a good reference either way. a few simple tweaks and you can get it running correctly.

What do you mean it "grinds" horribly on the chainring? It sounds like this happens when you go from a "big-front-gear / biggish-rear-gear" to a "small-front-gear / same-biggish-rear-gear"? Is the chain rattling on the front derailleur?

Note that putting visible wear into a chainring takes a LOT of miles. Not all of the teeth on the chainrings are shaped the same way.

As others have said, a big/big or small/small combination will cause some grinding noises since the derailleur and the gears simply can't accomodate such a large angle of the chain. But the small/biggish gears should work silently.