I've got an 03 banshee with LRD pipes, and K&N, but that's it. I raced a pretty unexperienced rider on the yzf450 and it wasn't even close. a few minutes later a new honda 450 wanted to race, granted it wasn't broken in yet, but the rider seemed good but I beat him up the hill by 4-5 bike lengths, and the yz450 was 3 bike lengths behind it. They were both stock; but like I said it wasn't close.