If you want to quiet your exhaust down a little, you can install a Kolpin atv stealth exhaust system. I hung one
from the pre-runner back bumper. Following is a review I wrote for Cabelas:
"I mounted this on my Polaris Rzr. It only quieted the exhaust noise 20% to 30%. It is not as good as advertised, but it did quiet the exhaust noise enough so that the driver and passenger can carry on a normal conversation. The only thing you can use this for a stealthy approach is to a tree in the forest."
Following is the advertisement by Kolpin: This innovative new exhaust system puts a muzzle on the noise from your ATV. The ATV Stealth Exhaust System cuts in half the noise output from an ATV, allowing you to reach your hunting spot with a minimum of disturbance to wildlife. This quiet system also is ideal for wildlife photographers or farmers and ranchers who need to check on livestock without spooking them. You won't sacrifice power, either. In fact, Dyno test results, on some models, have revealed an increase in mid-range power and overall performance. The universal design fits any ATV with a four-stroke engine. Comes complete with the mounting hardware and detailed instructions.