Yes, I agree companies detune, I remember when the XCR 600 first came out with the Variable exhaust valves, and factory triple pipes, and they were testing down in MN, and it was beating the storms, so they had to detune it allot. It seems now though with the technology, and strength of new metal compounds they are running them closer to there limits every year. As far as the rev 600, or any rev for that matter, there doesn't seem to be very many aftermarket pipes out there, so that tells me ski-doo got it pretty good with the factory setup, silencers seems to be the only thing allot of people change out on them, but they are pretty minimal gains, although I was talking to my dealer, and he said there is a company out of British Columbia, Canada that developed a new silencer that is getting gains of 8-10 HP at the track so that's pretty substantial for a silencer replacement. I did it more for the weight reduction, and sound than anything else.sesnopro said:every sled manufacture detuneds to a certin point. they do it so it is easyer on the engines. if you cant find an aftermarket pipe getting them ceramic coated would be your best bet.