To make a long story short my 01 zx6r has three litres of 15w40 rottella t and one litre of regular penzoil 5w30, do you think this will pose any probs with clutch????/
You're worried about the clutch slipping because of the SM pennzoil? I wouldn't, but if it happens you'll feel it, and you're out a whopping 11 bucks for a drain and refill.
Now, if it was the other way around (three quarts 5w30 and one quart Rotella) then that might be less of a good idea. The 5w30 is "Energy Conserving" and has the potential for clutch slippage. Has the potential. Not that it would.