the shock on these bikes vary greatly, the cbr400 nc23 shock will not go on a 29 and a 29 shock is different to a mc21......although i dont know abot the 23 shock going onto a 21.
also the 29 shock is the same as older model cbr600
_________________
MC21SP - Roth-tax
CBR400 - track
MC21R - sold
MC21SP - sold