Soo according to the garage i take my bike to have have worn cams on the left hand side (piston 1/2), the guy says that this is most likely occured from that side being starved of oil, so i asked him if getting my knee down a lot on the right hand side could cause this, and he said it's most likely, yes. just thought i'd share this, as its a new one to me, maybe its not true, i dunno.

Mike