The 2017 Yamaha Sidewinder X-TX SE is an all-new Extreme Crossover model powered by a new, turbo-boosted, 998cc four-stroke Yamaha engine – the most-powerful stock engine that’s ever been stuffed into a snowmobile. Yamaha claims at least 180 hp from sea level all the way up to 10,000 feet, but dyno pulls by several independent shops have shown it produces more than 200 hp.
The engine introduces a lot of technology to snowmobiling to make it durable and powerful. That list of technology includes a ceramic composite cylinder coating for abrasion resistance and a different coating on the connecting rods, also to prevent wear. Oil squirters help keep the piston domes cool. Engineers sought more power and a quick response with a high-end turbo unit, high-tech engine control unit and triple throttle bodies – the first such fueling setup for a factory turbo engine in a snowmobile.
The Sidewinder is based on the Yamaha SRV chassis that it shares with Arctic Cat, but it has refreshed look with new bodywork for 2017 to help control airflow – which is especially important for a boosted engine – and an LED headlight. Its 141-inch X-TX suspension is an uncoupled design that forgoes torsion springs in favor of a FLOAT shock to support rider and machine weight. The Sidewinder X-TX has the same seat and front suspension as most trail-focused SR Viper models, and dual-runner Tuner III skis bolted to the spindles.
2017 Yamaha Sidewinder X-TX SE: On-Trail Performance
For a machine whose roots lie in the mountain category, Yamaha Sidewinder X-TX SE owners will have good days on the trail behind the handlebars of these machines.
Engineers and marketers for Yamaha have made a lot of noise about the lag-free nature of the Sidewinder X-TX SE’s Genesis 998 Turbo engine since its media introduction last winter, and that’s a fair claim. But, like any other engine, it has a power curve that causes the engine to produce different amounts of horsepower and torque at different RPM, so there are varied levels of response based on vehicle speed and load.
We felt some delay from zero to 10 mph, which was more of a deficiency when off-trail. Squeeze the trigger when traveling faster than that speed and all bets are off – except for whether the Sidewinder X-TX will be the first one to the other side of a lake. It really lights up at 20 mph. The longer track helps harness all of that power and creates a reasonably balanced and traction-ed machine that’s pleasant to drive down a trail. The powertrain feels well in tune with the driver’s throttle thumb so the two can stay in synch.
When driving in a straight line, the machine goes like a rocket. Fortunately, the power delivery is easy to manage thanks to the engine’s high-tech boost and anti-engine brake systems. Like other Yamaha four-stroke engines, the powerband is linear and that makes it surprisingly easy to manage on the trail.
The Sidewinder X-TX cornered flat and its unique, dual keel skis held a generally good bite in the wet, packy snow we experienced during our test ride near West Yellowstone, Montana, in February 2016. It should be noted, though, that we often get mixed results with Yamaha Tuner skis. Even though the skis pushed through some turns, the front end maintained a planted, stable feeling despite occasional inside ski lift through other turns. The front end felt rough over stutters with 80 psi in the ski shocks, so owners should do themselves the favor of reducing the pressure from that stiff factory setting to about 65 psi, like we do with FLOAT 3-equipped Yamaha and Arctic Cat sleds.
2017 Yamaha Sidewinder X-TX SE: Off-Trail Performance
The 2017 Yamaha Sidewinder X-TX SE climbs and crawls around in the backcountry pretty well and it gets good rear-end traction so riders can carefully and methodically maneuver through the trees, but it’s just not a playful/extraordinarily fun machine for that type of riding. It comes down to its weight, and there’s no denying this machine has a disadvantage compared to the other Extreme Crossovers when riding off-trail.
Riders absolutely will be able to make their way through the woods and follow their buddies among the trees, through coulees, across swamps and along power lines – we did – but X-TX pilots probably won’t have as much whip-it-over here, throw-it-over-there fun as riders on lighter and more maneuverable two-stroke-powered snowmobiles.
Small people can make the machine work, but this machine will be best for big guys who have more leverage, mass and muscles to make the powerful machine do what the driver wants it to do. Wider skis from the M-TX lineup would help this machine by improving flotation and potentially making it steer a little lighter on ungroomed and unpacked surfaces.
When the play areas opened up or for uphill climbs, it was fun to make use of the Sidewinder’s enormous powerband that, since it’s turbo-boosted, was unaffected by altitude. It will make molehills out of mountains (or power line inclines). Constantly going in and out of the throttle while boondocking, however, became tiresome in a hurry.
Outside of confined areas where riders are able carry enough speed to stay on plane, they won’t notice the extra mass, and they’ll find that the machine is playful for carving, especially on flatter terrain where gravity isn’t pulling the machine downhill. The Sidewinder X-TX rolls up onto one ski and balances in that position fairly easily. Ergonomics work well they enable Sidewinder X-TX drivers to move forward in the cab and influence the machine. The sculpted console is clean so it allows easy mobility when the knees and legs are moving forward and back, and when jumping from one running board to the other.
Highlights of the 2017 Yamaha Sidewinder X-TX SE
Impressive powertrain is smooth and fast
Stylish new bodywork
Yamaha’s history of rock-solid reliability
A fun trail runner