2008 powder sled evaluation

AmSnow.com is now SnoWest.com

The purpose of AmSnow's Powder Sled Evaluation is to see if our impressions from our March ride on prototype snowmobiles holds true.

At the start of the 2008 season, AmSnow's Mountain Team cited Polaris' 800 RMK Dragon 153 as its Best-of-the-Best mountain sled. We wanted to verify our choice with production models.

Traditionally, we have performed our Powder Sled Evaluation on mountain snowmobiles that have the best dealer setup for altitude and conditions, which means a dealer can make changes to suspension, clutching and, if need be, carburetion or the electronic-fuel-injection system; only OEM parts can be used. We also weigh the snowmobiles in their dry configuration - no fuel, oil, coolant or chaincase oil.

This year we did things differently.

A new approach
To make sure they were broken in, we careened on our test fleet for one day, working through real-world riding in the crooks, mountains and valleys near Driggs, Idaho. Then, 5 days later, we hauled the snowmobiles to Teamwork Motorsports, Rigby, Idaho, to have Ron Williams, a certified Yamaha, Polaris, Ski-Doo and Arctic Cat technician, verify the snowmobiles were in stock condition.

We wanted to ride 'em how they were boxed. This means we nixed best dealer setup as we wanted to test each OEM's build-and-ship specs for the Polaris RMK Dragon 800, Arctic Cat M8, Ski-Doo Summit 800 and Yamaha Nytro MTX; these are the Big Four's most popular powder sleds.

So, no changes to the primary or driven clutch, to the EFI or carburetors, no lengthening or shortening limiter straps, no increasing or decreasing shock air pressure, no flipping tracks and no adjusting shock pre-loads. Heck, we even made sure the sleds used OEM oil. Williams, with tech manuals in hand, assured us all four were in their OEM configuration. As was a Cat M1000 we had in our stall. We wanted to give it a fair eval too, but did not compare the M1000 to the 8s and the 4-stroke Nytro.

After the inspection, we weighed the snowmobiles in a ready-to-ride condition, fully fueled, with engine and chaincase oil at max and engine coolant topped. This is how folks ride 'em. Prior to the weigh-in, the snowmobiles sat in a warm shop for 24 hours to dry (refer to the applicable chart).

After we documented the wet-weights, we conducted turning radius tests (refer to the applicable chart).

With these tests completed, we loaded and sped off to Island Park, Idaho. There in the backcountry, we found ridiculously deep powder on top of a firm base; powder depths were 3-4 ft. minimum. Temps were in the low 20s with steady snows. Perfect conditions for riding, not photos.

We began our ascent testing each snowmobile's trail capabilities by pounding the moguls with our 150-horse hammers. Our ride included everything hard-core mountain riders do. We next set up a hillclimb course, complete with gates and timing lights; we had a two-thirds scale Rocky Mountain Snowmobile Hillclimb Association course.

With the gates set, each of the five test drivers were allowed two practice runs. After the practice runs, each driver rotated through the five sleds - twice - so we could record elapsed times (ETs) electronically. Each driver's best time for each sled was used to calculate the averages. We did this to dial out driver error. Simply, each driver's best ET on each sled reports optimum performance for the day at Keg Springs, Island Park, Idaho.

Nine days later we were back in the mountains near Driggs, Idaho, for more seat time. All-in-all we spent 3 very full days working through this eval.

So, we have data: ready-to-ride weights, turning radius and ETs. Plus, we have test rider comments. Drivers included: Matt Allred, Kevin Allred, Casey Allred, Brandi Allred and Dallas Poulsen, who graciously lent us his stock 800 Dragon for several days of flogging.

The following evals stem from both our quantitative and qualitative testing.

Dragon RMK
The Hits - Easy to control, excellent balance and light feel through the handlebars. Handlebar and seat height are perfectly matched for extreme maneuvering and transitioning from sitting to standing. The motor is economical, which is good when a gallon of gas costs $3. The Dragon's running boards are traction savvy and clean well of powder and ice. Its Walker Evans air shocks keep the sled positive in the whoopy moguls and allow the rear skid to float in the deep. For its first year, it is a successful snowmobile from Polaris. The numbers are all very close, but using those and our riding impressions, we remain sold on this being AmSnow's Best-of-the-Best mountain sled for '08.

The Pits - In ultra-deep powder, snow chokes off the exhaust pipe, especially when stuffing the right side into a sidehill or sweeping a hard right-side roll; the motor loads, coughs and sputters. Some feel the graphics are too cartoonish.

Driver Comments:
Dallas: Strong motor. Effortless sidehilling.
Brandi: Feels natural, just hop on and go.
All riders: It doesn't breathe well in 4 ft. of powder.

Arctic Cat M8 Sno Pro
The Hits - Vastly improved from '07; we like the weight loss and properly calibrated drive clutch. Its Fox Float shocks are a great upgrade. Camoplast's Challenger track hooks up and lifts the nose. It also propels the Sno Pro 8 nicely on the snow.

The Pits - The handlebars are low, low, low; they need to grow 3 inches. Though the Fox Float shocks are a premium shock, its factory settings are too stiff.

Driver Comments:
Dallas: Strong power band. Easy sidehilling, but poor ski pressure.
Brandi: Great running boards and ergos. Easy to maneuver.
Casey: The easiest sled to jump on and figure out how to ride.
All riders: Needs taller handlebars.

Ski-Doo Summit X
The Hits - The XP Sum 8 is a superb mogul masher, and when mastered, you can ripsaw a mountain in half. When the snow is deep, the Summit lifts its nose and accelerates nicely to float on top, quickly reacting to driver input. In addition, the sled is undeniably obedient to throttle input, making the throttle a great tool to navigate right- and left-hand turns around blowholes and gaping drifts. The 16-inch wide track seems to be more at home under the XP Summit than under the previous REV Summit.

The Pits - When barreling through deep powder and hitting rutty trenched up snow, the nose gets nervous. The front doesn't stay nailed down when navigating righty tightys and lefty looseys on hard-pack ascents or descents. Its 44.8-in. ski stance (with swaybars) makes it feel heavy when reefing it over on its side in hard-pack. Like the Dragon, when powder covers the hood, or when the pipe is stuffed into a powdery sidehill or into a deep right-hand sashay, the motor hiccups and wants to die. Lastly, the Sum 8 X has an overly-stiff throttle pull.

Driver Comments:
Dallas: It's on target in the deep powder.
Casey: Fun in the powder where it hooks up well. Handles deep snow extremely well. Attacks the mountain.
Brandi: The front and rear suspension give the snowmobile a comfortable ride on the trail.
All riders: The front end becomes unpredictable when moving from powder to deep-rutted, hard-packed snow.

Yamaha Nytro MTX
The Hits - For being a heavier sled (not as heavy as Apex and Vector Mountain) Nytro feels light. Some of our riders felt it handled like a 2-stroke. With its tail-dumped exhaust and superb intake system, Nytro never faltered in deep snow.

The Pits - Running boards load up with snow, they do not clean off. When pulling hard turns in chest-high powder, weight overcomes momentum and the sled will roll over more than its pilot desires; the track washes out and you are stuck. Like the Summit, it has a stiff throttle pull. Lastly, its short windshield is inappropriate for deep powder riding, it wholly directs the powder into the driver's face! We suggest a taller shield. The Nytro's reverse lever is hard to grab with a gloved hand and is clunky too.

Driver Comments:
Dallas: Needs more ski pressure.
Casey: Not my choice for serious mountain climbing. Handles well when mashing through really deep powder though.
Brandi: Smooth suspension, especially on bumpy trails.

Arctic Cat M1000
The Hits - Big power. The 162 is the best track length for this motor. Motor is smooth when throttling it up, not snappy like its smaller sibling, the 800, but smooth like an electric motor.

The Pits - Like the 800, it needs taller bars. Cat could shed some weight off its chassis too. The exhaust outlet plugs and chokes the motor when the sled is rocked to its right side in deep powder or on right-side cuts across a slope with deep powder. This creates a dicey situation when momentum is needed to finish a sidehill run.

Driver Comments:
Casey: It is too heavy for me. Thousand power is best for serious hillclimbing.
Dallas: Ski-pressure is lacking.
Brandi: It's heavy, but when on full power in the deep snow, it feels light.
All riders: Needs a riser block for the handlebars and a weight cut. (See the 2009 Sneak Peek, it appears Cat has been listening to our comments!)

Special thanks: To Ron Williams at Teamwork Motorsports for his technical expertise, Ski-Doo and Steve Cowing for supplying the Summit X, Wade West and Yamaha for the Nytro MTX, Kale Wainer and Arctic Cat for the M8 and M1000, and Dallas Poulsen for the Dragon 800, the Preston Pride Hillclimb Association for the timing lights, and Rexburg Motor Sports for its digital/electronic scales.