Whether it's a segment within a segment, or a whole new way to look at snowmobiling, the 2009 Polaris RMK Assault is a forward step in the evolution of high-performance, quality-suspended snowmobiles.
What is it? The 2009 Assault rides in the proven RMK raw chassis (with nose pan and bumper updates) and is powered by the punchy 800 CFI twin. The 15x144x2.125 track is stiffer and more aggressive than any previous Polaris offering. The ski stance is wider, offering a range of 41-43.5 inches. The Assault features the new Pro Taper handlebars that are taller than the '08 RMK's, but without the sidehill hoop. The Pro Tapers also feature positive-stop bar hooks. These hooks have a 90-degree hook angle rather than the 45-degree hooks on the '08 RMK bars.
But the feature that packs the most punch for both the Assault and the riders it's targeted at, is the suspension. The Assault has possibly the most aggressively-valved suspension setup of any production snowmobile. Fast-paced, top-level riders who have always been disappointed in stock suspension component performance will fall head-over-heels for the Assault's shocks. Randy Sherman, a pro backcountry rider known for his air time, seemed quite impressed with the Assault's aggressive ride at the model's catalog shoot earlier this year. Thanks to piggyback remote-reservoir Walker Evans air shocks on the front and high-performance Walker Evans shocks on the skid, the Assault can rail through deep holes, square-edged bumps and rhythm sections better than just about any production sled we've ridden. It might even put a full-blown race sled to shame.
The rear suspension also gets new straight rails which are half a pound lighter each side and stronger-especially at the rear end of the rails where other rail styles have been prone to bending or breaking under heavy abuse (the RMK and Dragon feature the new beams, but are still tipped up in the rear). The Assault's slide rails also have braces between the rear scissor arm and the mid idler wheel for enhanced durability.
The Assault and all RMKs get a new magnesium chain case cover and lightweight wave brake rotor. The magnesium cover is as light as plastic but much more durable, and the wave rotor sheds one pound over previous versions.
The plastic body work of the belly and nose pan has been completely re-worked on the Assault and RMKS. Basically, the plastic bumper was replaced with a sturdy aluminum tube and the one-piece belly pan is now a three-piece modular system that maneuvers through deep snow better and is easier and cheaper to replace if need be.
The Assault's 2.86-pitch 15x146x2.125 track is all about traction. This is one of the sled's components that really distinguishes it from standard RMKs. It has wide, stiff lugs with ridges and edges designed to chop into the hard snow and grab a solid bite. It provides the maximum traction in packed or set-up snow conditions, although it's at a trade-off for deep snow mobility. But the Dragon RMK covers that niche.
Our impression of the RMK Assault boils down to this: If you compare our market to the dirt bike market, we're all pretty much riding trail bikes like XRs and WRs. There hasn't been a consumer model that compares with the CRF, KXF, YZF and RM-Z model dirt bikes; at least in the suspension department (we do have the best engines). However, now there is a model anyone can buy that features the best in pro-level suspension, ultimate traction, stable stance and the highest-quality components found on Polaris snowmobiles. The RMK Assault has the potential to open the flood gates on the freeride segment.