This is the latest and greatest offering of mountain snowmobiles from the four manufacturers. All with long tracks, big horsepower and super-lightweight, these machines are tailored for high-elevation deep-snow riding. We count our lucky stars each time we ride because we have access to incredible mountain terrain for riding these almost daily.
Once a year we put all our sleds on the mountain at the same time though, and try to determine which is best in our Real World Powder Eval. Determining a winner is always difficult, so we run the sleds through a series of closely monitored tests to see how they compare in different environments.
Once again this year we had a great group of snowmobiles with the top mountain sled from each of the four OEMs. The Arctic Cat M 800 Limited is in its second year of the new ProClimb chassis and is updated with a new deep-lug track and narrower front-end. The Polaris Pro RMK is vastly updated for 2013 with a host of improvements, including a belt drive, carbon fiber over-structure, new running boards and seat.
New this season is the Summit XM, which is a greatly improved version of the XP with new plastics, pivoting T-Motion rear suspension and FlexEdge track. The Yamaha Nytro MTX used in the test features the Yamaha-approved accessory rear-mount MPI turbo kit for a healthy power boost.
For several years we have conducted the Real World Powder Eval in Alpine, Wyo., as this area offers such a diverse range of terrain in a small area, plus the locals are always very welcoming. So we headed back to Alpine and set up shop at Lincoln County Customs and checked into the Flying Saddle Resort. The first day we brought along Riley Jensen to give a female perspective on the machines along with regular AmSnow mountain test rider Josh Skinner, LCC’s Chad Jorgensen and local Jay Mentaberry. With epic blue skies and frigid temperatures we sought out the deep snow.
Using a series of tests we set out to determine which machine performs best. Arguably the most complex attribute to quantify is sled handling because handling is very much a matter of personal rider preference. However, in an effort to quantify handling we set up a winding, bumpy, uphill hillclimb course and sent each of the four riders up the course on each of the four sleds using an AIM GPS timer to measure the time between start and finish.
To adjust against riders running the course quicker after practice we rotated the machines so that each rider’s last run was on a different machine. After 16 runs from the four riders we compared results.
The quickest time of 18.84 seconds came from Jay Mentaberry on the Summit X, but the average time for each machine from the four riders put the Pro-RMK in first, M800 in second, Summit X in third and Nytro MTX Turbo in fourth.
In each case, aside from the Yamaha, the test rider recorded their fastest time on the machine that they had spent the most time riding, proving that out of the 800s the most capable machine is the one with the most capable rider.
Colder temperatures rolled into Alpine on our second day of testing so we were thankful to be able to spend some time in the warm LCC shop weighing the machines. We had filled all the sleds full of fuel and oil at the end of the previous day’s riding and left them in the shop overnight to thaw all the ice and snow off. Complete with a spare belt each machine was weighed completely ready to ride. Using an analog dial scale we lifted each sled using an overhead hoist and recorded the ready-to-ride weights.
At 525 lbs. the Polaris Pro RMK was the lightest, followed by the Ski-Doo Summit X and M800 both at 575 lbs. and the Nytro MTX Turbo at 645 lbs.
The snow on our first test day had been fairly hard, windblown and tracked up, so we really needed to find some fresh snow to test these machines’ climbing abilities. We headed to one of our favorite honey holes and put some of the first tracks into the area, getting in there was a a challenge as there wasn’t quite enough snow to cover all the bushy undergrowth.
After several stucks we finally made it to the riding area and into much improved deep snow conditions. We found a wide-open hill with a good long incline and set the AIM GPS timer to record a 1/8-mile test. Starting from flat we ran each sled on a parallel fresh line straight up the hill.
The turbo-equipped 162 Yamaha shined in this test and recorded the quickest time of just 13.98 seconds, followed by the Pro RMK at 14.81 seconds, the M800 at 15.17 and Summit X at 16.04.
Digging deep into the data we could see how the machines achieved their times, at the start of each run we would mash the throttle causing the sled to start digging into a hole and then accelerate out. The 60-foot times basically showed how quickly the machines could get out of a trench and back atop the snow. The lightweight Pro-RMK and deep-lugged M 800 were the quickest off the start, but by 330 feet the Nytro was on full boost and stretched out a lead it maintained until the end of the 1/8-mile test.
Surprisingly the Ski-Doo finished last despite having the highest surface area (16-x154-inch) track of the 800s and a powerful engine, the Ski-Doo seemed to trench a bit more and lift the skis more, likely hurting its hillclimb performance. All four sleds were separated by a mere 2.06 seconds and the 2-stroke 800s separated by just 1.23 seconds, showing how evenly matched these sleds really are.
It’s a wrap!
Taking a win in the handling course average, a win on the scales, second in the hillclimb and the average win among our testers’ opinions, the Polaris Pro RMK once again lived up to its name of Rocky Mountain King.
The other two 800s from Ski-Doo and Arctic Cat were close in every test and tied overall when the scores were averaged. The Yamaha laid down a really fast time on the straight hillclimb, but in the other tests its weight hindered performance slightly. The machines are so close on performance that differences can become almost negligible in comparison to rider ability, as was proven in our hillclimb test.
Rider skill is the biggest variable to how high up the mountain or deep into the trees a sled goes. These machines can make it through incredibly steep, deep and complex terrain, the question is, can the rider make the sled perform?
We had a great group of sleds this year that all performed really well. They are so close that it really comes down to what each rider personally prefers and having confidence in the machine to know how it is going to react in different situations. My favorite is the Ski-Doo Summit XM because of how responsive the chassis is to rider inputs and its a fun engine. Second would be the Pro-RMK. It’s a great machine, but I’m not overly stoked on its build quality. Manufacturing issues have plagued the 2013 Pros and it’s extremely frustrating how the belt gets wet on left hand sidehills. The Cat is much improved this season and the new deep-lug track with the trusty 800 engine is a solid combination, plus it’s cool to see Cat working the bugs out of this new chassis and putting it back in contention. As for the Nytro, yes it’s heavy and more work to ride, but cracking the throttle wide-open on the supercharged Yamaha sure is a blast. The sled is really fast and in the right terrain and group of riders it too can be a fun ride.
The new Summit may not be the lightest Mountain Horse in the stable, but it sure performs well and is fun to ride. I think Ski-Doo really hit the mark with all the improvements to the XM as compared to the previous XPs. All this with a fit and finish that rivals Yamaha’s legendary reputation puts the cherry on top for me! The new Pro-RMK from Polaris is very light and rigid. The white livery on our sled also looks great! Polaris did a great job reducing weight again, although I don’t know that it improved the ride. Broken driveshafts and contradictory break-in sequences for the two belts on this sled kept it from No. 1 on my card. Also the Pro Taper handlebars are too wide, a bit high, and the running boards are too narrow and manage to still gather ice despite the new cutout design. It›s still a fantastic sled and continues to perform neck to neck with the XM. I really enjoy the ProClimb chassis and brute strength of Arctic’s 800 mill. In fact, if it wasn’t such a competition to get to the top in the DEEP stuff between mountain riders, the Cat may have gotten my top pick. The suspension works great in the rough stuff and the sled is a blast to ride! The Cat is my favorite “daily rider,” but it doesn’t seem to work quite as well as the XM and Pro in deep powder. New skis might help? While belt issues are much less prevalent this year, they still explode from time to time. A particular annoyance I have with this sled is the seeming lack of attention to detail and finish. Screws vibrate out of their homes, strange rattles are heard at idle and the side panels are unnecessarily difficult to remove and replace. And, don’t get me started on adding oil to the reservoir! That said, the Sno Pro LE is dead sexy and is awesome to play around on. I always look forward to seat time on this sled. The Yamaha has stump pulling power in a dated chassis, but thanks for the BNG Yamaha! If you can keep the snorkel intake clean it runs quite well, but if the snorkel is clogged, I’d rather ride my old 570 Exciter. I know Yamaha has another industry leading mountain sled in them, or at least one that performs as an equal to the other OEM’s offerings. The question is: How long do we have to wait for it to launch?
In my opinion, all of the sleds ran great on the mountain. They all had their weak and strong points. As far as maneuverability I think the Pro chassis had great handling, and was a little more forgiving than the other sleds. It also had a sweet spot that you could hold on any line. The Arctic Cat has great power, and was just a step down from the Polaris as far as control. As for the Ski Doo, it was a great tree sled, and held the trails hands down the best. It also had responsive power for tricky pulls. The Nytro had big power, and rode pretty well when you were on the throttle. The only downfall to it was that it was a bit tougher to handle on slower moves and was really heavy to turns out of a line.