On my two road bikes I've noticed lots of scratches developing (and getting worse) on the drive-side chainstay. It's right in the pedal/shoe area and below the little plastic cover they put on to protect it from the chain. The deeper ones go through the paint. I certainly don't notice any contact when I'm pedaling, but I can't rule it out. The non-drive-side is spotless. Should I be concerned about this? I hate to be scratching up my new bike.