I have a 500 scammy 4 stroke, and would like some more power, but is a pipe really going to help out? I have been on different web pages that say 4 to 6 hp but I know from dirt bikes that pipes on 4-stroke don't allways increase performance but they always increase noise!!!

 

a pipe and air kit will help out. they sell silencers if you dont like the noise.

 

I can only talk about the HPD Powermaxx exhaust because that is what I have. I will tell you that you will feel an increase in low to mid range torque. I really didn't gain any top end speed with it though. However, it sounds mean when flyin down the road. The HPD pipe is almost twice as big as the stocker so it definately flows better. You won't see the same difference as you would with a 2 stroke[img]i/expressions/face-icon-small-sad.gif[/img] You will notice it more with a clutch kit in addition to the exhaust. Just my .02

 

i bet your best thing should be to trade it for a piped 400,then you'll have the power you looking for...same chassis.
a pipe and jet thing made a slight differences on this engine.