Funny rubbing sound

[BikeCrazyAgain]

When I'm riding, I hear a repetitive noise that sounds like metal rubbing near the front cogs (apologies if my nomenclature is incorrect). I have a Specialized Ruby with a compact double (50/34) and 10 gears (12-27) in the back. I spend most of my riding time on the smaller chainwheel and use the full range of gears in the back.

So my question is this: am I wrong to use the higher gears in back with the smaller chainwheel (small/small), even on a compact double, and could that be the source of the rubbing sound? Should I instead change up on the chainwheel and down in back for the same speed/cadence? Or is it more likely that something is out of adjustment? My bike is only 4 months old, so could it still be new enough to need more frequent adjustments?

Or some combination of those things?

Thanks,
Patty

[Bill]

First the chain moves when you shift the chain. So the chain might be rubbing against the side of the front derailler. A mere slight adjustment in the lever position would make the noise stop. This is how gears should be utilized .... http://bikeride.com/gear-shifting/

[BikeCrazyAgain]

(07-22-2010, 07:24 AM)Bill Wrote:  First the chain moves when you shift the chain. So the chain might be rubbing against the side of the front derailler. A mere slight adjustment in the lever position would make the noise stop. This is how gears should be utilized .... http://bikeride.com/gear-shifting/

Thanks, Bill. That is what is sounds like. I'd read or saw or heard somewhere that the Shimano shifters permit a slight change in position without an actual gear change with a half-step sort of action on the lever, but I don't know where I heard that or how true it is. I'm riding later today, so maybe I'll try it. I was thinking to put the bike up on the rack and see if I can duplicate the sound that way, too.

Thanks,
Patty

[AndrewB]

(07-22-2010, 12:08 PM)BikeCrazyAgain Wrote:  Thanks, Bill. That is what is sounds like. I'd read or saw or heard somewhere that the Shimano shifters permit a slight change in position without an actual gear change with a half-step sort of action on the lever, but I don't know where I heard that or how true it is. I'm riding later today, so maybe I'll try it. I was thinking to put the bike up on the rack and see if I can duplicate the sound that way, too.

The Ultegra 6700 does for sure, from personal experience. However, this third position is on the outside, so that would be for the larger crank to hit more gears.

Maybe your fd is misaligned. But ideally, on a compact crank, you probably don't want to be in the smaller rear cogs while on the small crank for long.

The big crank is better, anyways. More links per spin.