I absolutely love the ZZR600. Extremely comfortable, powerful, and handles pretty well. However, upshifting from 1st to 2nd gear is often accompanied by a loud "clack". it seems unusually loud, it shifts fine, just loud in that gear range. it could be that i'm not in the correct RPM range, but i doubt it. any one have an idea of what is going on? the bike has 3100 miles on it.