My bike is completely stock and it kept up pretty damn well with a Suzuki Bandit (not sure what displacement, it definitely had to be a 600 or more though) and an R1 in a straight and some winding roads the other day. I dare say if I didn't have a passenger and were a better sport shifter it'd be even better yet. That was my most spirited riding I've done so far, I love my bike! The best part is I won't end up with the back pain like they well