supertrapp exhaust

I believe the theory is more discs make it quieter while less discs provide more flow/power. It adds adjustability so you can lower sound for OHV areas, or increase power when you go to the track. Never owned one though, but talked to a few guys who had them.

It is all about tuning back pressure. I was cleaning out a junk drawer in my garage a while back and found a few of those discs left over from my brothers old 1985 XR200. We used to mess with the number of discs and also ran it with none but never really knew if it made much difference.

From http://supertrapp.com/technology

A signature feature of SuperTrapp exhaust systems is the diffuser disc technology, created and patented for the XDUSOR, the first motorcycle exhaust product sold by Moller in 1971. This technology allows the rider to adapt their bike, or ATV, to a specific riding environment. This is accomplished through a series of discs with a precisely aligned diameter that form the exhaust outlet. By adding or subtracting discs, the rider can tune the powerband and sound of their machine in just a few minutes with basic hand tools.

Removing discs decreases the exhaust opening and increases backpressure. This effectively decreases the powerband to create more low-end torque. It also decreases exhaust tone and enriches carburetion.

Adding discs increases the exhaust outlet and decreases back pressure. This widens the powerband at the top end. It also increases exhaust tone and leans out carburetion.

All SuperTrapp systems come with installation instructions that indicate the recommended number of discs for each application.

Guess I had it backwards. lol