RUMFORD – Modifying a snowmobile’s exhaust system to spike engine snarl under the guise of increasing horsepower is fast becoming a lose-lose proposition in Maine’s leisure-trail sled world.

It may jack up the coolness factor and intimidation levels, but screaming sleds are undermining years of work by snowmobile clubs and legislators to secure trail access.

Not only is it illegal in Maine, but excessive sled exhaust noise is leading annoyed landowners to close their property to snowmobile traffic. It’s already happened this winter in Peru.

In a state where snowmobiling contributes an estimated $350 million annually to the economy and where 95 percent of its 13,500 miles of snowmobile trails are on private land, trail closures worry people.

For the Maine Warden Service, it’s crackdown time, for a growing behavioral problem the sport can no longer tolerate, Sgt. Rick Mills of Andover said.

“We’ve been addressing it now for two to three years and, well, we’ve been kind of 50-50 on the enforcement end, issuing just a warning depending on the history of the snowmobiler and how long he’s had the sled, and so on,” Mills said Wednesday.

“But we’re starting to get a lot of complaints from landowners and from families that have trails by their homes and they’re just sick and tired of the noise. So, we are going to try to crack down on that.”

Cracking down means a heightened presence along trails and more aggressive investigations by wardens trained and armed with decibel-reading devices.

Although the noise problem is statewide, Mills said it’s more prevalent in places where most snowmobiling occurs: Northern Franklin and Oxford counties and northern Maine in Aroostook County.

“Our goal is fair and consistent enforcement across the board, and, you know, if a guy goes to Stratton and he’s got a loud pipe, I expect him to get a ticket. It’s the same for a guy in Rumford,” Mills said.

Wardens say they’re not out to get sledders with borderline-illegal exhaust systems. They’re after the guy they can hear coming from three miles away.

Unlike the early years of snowmobiling, when sleds were slower and roared like chain saws, today’s snowmobiles are manufactured with hush technology. They’re specifically engineered for quiet.

According to the International Snowmobile Manufacturers Association, today’s snowmobile under full throttle emits the same sound level as a truck pulling a camper or an off-road Jeep traveling at constant highway speeds while applying very little throttle.

Maine law states that all sleds made after Feb. 1, 1975, and sold in Maine must limit total noise to not more than 78 decibels at 50 feet as measured by Society of Automotive Engineers’ standards.

Sleds made a couple of years earlier are restricted to no more than 82 decibels. Sleds built before Oct. 1, 1973, aren’t subject to a noise level, but cannot be modified.

Violating the laws through exhaust modifications is a civil penalty that carries a fine of a few hundred dollars.

What wardens are finding and landowners experiencing are more people removing original equipment and replacing it with after-market racing exhausts, according to Mills and Dan and Joe Brissette, the father-son manager and salesman of Arctic Cat dealer Mountain Valley Sports in Rumford.

“Normally, it’s an attempt to increase the horsepower which, in turn, increases the noise. Some of (the desire) is just noise and a lot of it is psychological. They think it increases the horsepower, and it really doesn’t. But they think the sled goes faster.

“I’ve talked with some dealers who say it actually decreases horsepower, but (people) do it because they like the noise, the intimidation thing,” Mills said.

“We try to discourage anyone from doing it, just because we can’t afford to lose our trails,” Dan Brissette said. “Because of this, we just lost a trail in Peru that goes right through town and comes out on Pleasant Street. Every time we lose a trail, that’s less riding you can do.”

Typically, mufflers are removed and replaced with a smaller non-certified cylinder, but it’s the expansion chamber that determines peak power, Joe Brissette said.

“By changing it, exhaust gases go in the motor instead of out of it. You usually lose more horsepower if you change out the muffler,” he said.

The problem is mainly gender- and age-based.

“It’s your cowboy or your maverick on a snowmobile that wants to tweak his sled a little bit and he changes the pipes on it some. And some people use the sleds for trail riding as well as racing, so it’s a combination of things.

“But, you know, you don’t see many 60-year-old guys altering the pipes on their sleds,” Mills said.