try taking it back to the basics, if Ade got his sorted by larger jets (due to K&N filter and poss non stock exhaust) and the fact that Sam has had NEW carbs (which would have standard jets) have either Red or Sam got any form of mod to air filter, air box or can??
it sounds like you both have stutters at higher revs trying for max torque which really sounds like they are leaning out (too much air rather than too little fuel)
only my thoughts, good luck guys