Ski-Doo REV-XM, Summit SP 800: Carve Like A Pro

If you’re one of the snowmobilers who have criticized Ski-Doo REV-XP Summit models for being cumbersome boondockers or side-hillers, you owe Ski-Doo and yourself a ride on the 2013 Summit SP E-TEC 800R. Many changes — big and small — equate to major improvements in terms of handling and maneuverability in deep snow.

There have been updates made to the Summit XP chassis since it debuted for model year 2008 that significantly improved its backcountry snowmobility, but effects of those changes pale in comparison to the leap in performance that riders will feel when on board a new REV-XM-based Summit.

Throw a leg over the narrower seat and by transferring your body weight from one foot to the other on the running boards, you will notice the sled is easier to tip from side to side. A narrower ski stance also helps tip the sled, and new body parts and footwells make it easier to navigate the console and influence where the machine goes.

Take all of those new features and wrap them around the direct-injected Rotax 800cc engine and the 2013 Summit SP E-TEC 800R not only becomes a better mountain sled than the Summit of old, it makes better mountain-sled riders.

2 Degrees Cooler

A ball joint allows the tMotion suspension to twist inside the tunnel for easier banking and sidehilling.
A ball joint allows the tMotion suspension to twist inside the tunnel for easier banking and sidehilling.

Known for consistently developing cool technology that performs well, Ski-Doo’s tMotion rear suspension represents the most interesting mechanization in its 2013 snowmobile lineup. A ball-joint connection where the rear torque arm attaches to the drop link above the suspension rails allows the suspension to lean up to 2 degrees in each direction. Ski-Doo calls this ball-joint a swiveling rear drop link.

Farther forward in the rear suspension, a cross-tube within the front torque arm is split, allowing it to very slightly twist around the cross-shaft. This contributes to the flex of the tMotion suspension and improves overall maneuverability of the snowmobile. Parts twisting and flexing in the rear suspension might seem like they would present a maintenance or durability issue, but Ski-Doo says its engineers have conducted significant durability testing and they are confident in its design.

The ‘t’ in tMotion stands for “twist,” and BRP’s intent with this new rear suspension is to reduce the machine’s resistance to banking in deep snow, a trait for which REV-XP-based Summits were known.

The Powder Max II track with FlexEdge has 2.5-inch lugs and is 16 inches wide, but its reinforcement grauser bars are only 12 inches long to allow the outside edges of the track to flex when carving or side-hilling. Summit SP E-TEC 800R is available with a 146-, 154- or 163-inch track.

Summit engineers also focused on mass centralization when designing the new REV-XM chassis. By redesigning the side panel and structural member around the footwell, riders can put their feet 8 inches farther forward than the REV-XP, which puts the rider’s feet closer to the snowmobile’s center of gravity. New bodywork was designed to provide more clearance over the snow and all the points where the rider physically interacts with the sled were redesigned for more comfort and better performance.

Amateurs Become Experts

It’s surprising how immediately apparent the benefits of the tMotion skidframe and FlexEdge track are when rolling and maneuvering the sled in the mountain backcountry. Twisting 2 degrees one direction or the other might not seem like much, but it’s enough to cause a major improvement and make amateur mountain sledders ride like experts. Rolling into a sidehill is effortless and the sled balances well when it’s up on one ski.

An interesting characteristic we noted was the skidframe felt like it hit a stopping point when making slight turns while climbing. This was felt more often while traveling downhill, but it’s worth noting that the chassis seemed to roll in two stages: once to make the initial cut and another to get the sled to stay up on edge.

Cut-out side panels and redesigned footwells let the rider move farther forward than on REV-XP Summits.
Cut-out side panels and redesigned footwells let the rider move farther forward than on REV-XP Summits.

As part of the effort to improve interaction between rider and sled, Ski-Doo repositioned the gauge for better visibility while standing. Sightlines to the refreshed digital package are excellent; it has a modern look and high-quality appearance. The narrower/shorter seat makes no sacrifice in terms of comfort, but it results in easier side-to-side transitions.

Form is supposed to follow function, but form is function on the new REV-XM. Side panels were designed to slide through the snow to enable better maneuverability and easier roll-ups in powder so the rider can throw the machine on its side panel. With so many new factors on the fresh REV-XM there’s no way for us to quantify how much the side panels actually improve the new Summit’s snowmobility, but they certainly seemed to contribute to the overall-better Summit package.

Other interesting points about the chassis include the running boards that have been significantly opened up to reduce weight and improve snow evacuation. Extrusions along the top edge of the tunnel are three times stiffer, Ski-Doo says, to prevent sagging.

Like the Summit it replaces, the windshield is anchored with rubber grommets so it can pop off quickly, which prevents damage to the shield when the machine ends up upside down on the side of a mountain. The LinQ accessory mounting system is a fast way to mount luggage and fuel containers, and should be a big hit for backcountry riders.

FlexEdge and tMotion technology are only available in 2013 Summit X or Summit SP models. A Summit SP is easily distinguished by its black/orange coloration. Other than that exclusive color, different handlebars and each machine’s shock package — Summit SP has non-rebuildable HPG shocks, Summit X has HPG Plus dampers — the two models are virtually identical. Based on how well the SP performed for us in the powder, we think it’s a sled that will make a better mountain rider out of every snowmobiler who drives one.

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