I don't think everyone is disavowing "aftermarket silencers" at all .. there are companies that make lightweight cans that are as quiet as the stock exhausts....people are just saying think twice about putting the stupid-obnoxious 100dB+ can/pipe combos on ... I think at least.
I agree that the greenies will find and use every excuse they can, however. abnoxiously loud pipes provide them with an all too easy target. I look at how you used to be able to ride dirt bikes virtually anywhere around Casper WY (my hometown) and how over the last 20 years everywhere you could ride has been shut off due to noise complaints .... and it's a direct result of everyone thinking they had to take the baffle out of their muffler. You get 20 people with that mentality, and it doesn't take an acoustical engineer to realize you can hear that for MILES away.
The point those of us who speak out against the stupid loud pipes are trying to make is that having pipes that loud does NOT help our situation any more that it provides you with a performance benefit. I would really like to see some posted dyno results .... is 1/5 a horsepower worth an extra 20 dB and a riding area shut off? Not IMO ...
I am the last person whatsoever who is gonna defend the greenies, but one of the biggest problems I see amongst motorsport advocates such as most of on this site here are is that we refuse to use our brains and make the most obvious concessions about what we're doing, and then we get completley owned on it by the greenies ... one of these things are the 100+ dB pipes ... I think another thing is people with 4WD trucks and 4-wheelers that go tearing the **** out of the land where they shouldn't be, but that's a whole other argument in itself ...
I think it's really a copout to justify having obnoxious pipes with the mentality "well, if it isn't this, it'll be something else" for the sole purpose the loud pipes are a virtual enormous red flashing bullseye for the greenies to shoot at ....
I think now more than ever you have to really be intelligent about the whole situation, you can't just blindly do what everyone else does with the "F*ck the greenies mentality" because that just digs us all into a ditch even further ...
With that said, I most assuredly have a "f*ck the greenies" mentality but I'm also intelligent about off-road use and do everything I can to not abuse it.
I'm sure you guys will flame the **** out of me, but I really don't care
edit: Also, as a side note I do have an aftermarket silencer on my sled, but I sure can't tell that it's any louder than the stock pipe was ... it's actually quieter at idle I think....might be SLIGHTLY louder at WOT, but not too much. If I thought it was obnoxiously loud, I wouldn't be running it ...
But now that I think about it, I should email SLP to see if they've ever measured how loud their can for my sled is ... I am thinking it probably meets the same US Forrestry Service requirement of 96 dB that most aftermarket 4-wheeler exhausts need to meet to be "legal".