10-03-12, 10:47 PM
on the later fz1 you lose the exup valve with a aftermarket exhaust,on the later fz1 the exup valve does not give the better mid range power that the early fazer had using the exup valve,it is there mainly to quiten the exhaust so yamaha could fit a more free flowing silencer to help top end power,you will need to keep the servo motor plugged in,and you can either remove the cables or secure them so they wont catch or drag on something