hmm,i must be about 3 stone heavier than jamie,i think he needs to do the airbox mod as when i did mine it was from 9000rpm onwards when i noticed the real benefit of opening the airbox up.Today is the first time that i have seen a 21 close up and i didnt think that apart from the swingarm that they would be that different to look at,i through that the differences would be suttle,but they are dramatic,i liked the look of the 21 from photos but now ive seen one close up ive realised how nice they are,im going to have to get one as well.