I just bought a 2001 cbr600 f4 and have only ridden about 150 miles so far. I walked behind it yesterday and noticed a scuff on the left edge of the tire where it had been rubbing something. Upon further inspection i found it was rubbing the bottom portion of the rear fender close to the swingarm. Just sitting on the bike it doesnt touch but i can bounce on it and it does. I suspect its rubbing under hard acceleration and on dips/bumps in the road. Do i have a suspension problem, Tire problem, or a weight problem? 6'3" 245lbs. Rear tire is 195/55. Thanks in advance

 

I'd say you have an issue with the wrong size tire.

I think you should have a 180 55, not a 195. That tire is too big for that bike. Not only does it appear to be hitting something, it can affect the way the bike handles as well. It may even be too large to safely be mounted to the rim.

I'd suggest changing to the proper size tire.

 

I did a little research and i'm supposed to have a 180/55 like you said. its a shame that this tire is practically brand new! Guess its time for some burn-outs! On a side note i did find that the shock was set at its softest setting (1). I increased it to 7 and wow what a difference. I didnt realize it was handling so poorly.