A friends 07 with a race kit (the original one)said that when he is riding hard an at 6K revs and he gives the last twist of throttle the bike raises really fast close to 7k with no speed increase and the revs fall fast to 6k and then the bike pulls fine up to close to 7k, could this be clutch slip?
it all depends on how it's been ridden, and how much abuse the clutch has seen. but yeah, that sounds like a toasted clutch. "slipping in higher gears, and especially at higher speeds"
when i fried mine; i went with an energy one clutch kit (about a thousand miles ago) and am pleased with it.
Not to nitpick, but this is a roadside adjustment. This should be done first with a loosened cable, screw should be turned ccw until slight resistance is felt, and then turned cw 1/4-1/2 turn. Then the cable is adjusted to give 1/16 gap at the cable ferrule, not the lever. They are 2 separate processes. Simply adjusting the clutch will not cure a poorly rigged cable or vise versa.