www.zxrworld.co.uk

Can some explain to me what effect it has on the bike depending on size of sprocket you have,on mine it is 45 rear not sure what front is.

45 is the standard size rear on a zxr 400. On the front its 15. Alarger rear sprocket will give you a little extra acceleration but a reduced top speed at the redline. A smaller rear will give reduced acceleration and a greater top speed at the redline but only if your bike can actually pull and rev to the redline with that smaller sprocket. On the front this is reversed smaller is better aceleration and reduced top speed and larger is increased top speed but reduced acceleration.

bigger srocket on the rear means for easier wheelies