I got a stock 2008 cbr 600 and i was wondering if i could just put a front sproket -1 tooth on with out any problems. im still using same chain and rear sproket.

 

Usually it is recommended that if you change the whole drive set up at once (2 sprockets and a chain) but that is mostly to keep the mileage on the parts the same. with an '08 i'm sure that isn;t a real concern. Also, you will have to tighten the chain post-sprocket-swap, the smaller sprocket gives you more slack.

 

Should be just fine