At a quiet event populated by snowmobile media officials hungry for both burgers and racing snowmobile information, Ski-Doo unveiled big improvements for its 2012 MX Zx RS racing sled. The company promised big improvements in engine and chassis performance to propel its X-Team racers to a successful season.
Topping the list of changes is a new engine that delivers an additional six horsepower and better throttle response across the operating range. Among the long list of new components are a new crankcase, a new crankshaft and new cylinders — all of which are intended to provide higher horsepower. The engine was specifically designed to be very efficient from 8300 to 8800 rpm with a broad powerband along the way. A new fuel pump and hose routing improves fuel delivery to the engine, and new ECM calibrations complete the engine tweaks.
The front suspension was also analyzed to improve chassis performance and balance to better mate with the new skid frame introduced last year. New, taller spindles improve ski pressure and cornering, while the new powder coating will reduce snow and ice buildup. A redesigned steering post and bushings further reduce bump steer, while new upper A-arms create a steeper caster angle for improved front-end geometry. Ski-Doo says racers will notice much straighter tracking through bumps and better front-to-rear chassis balance.
The rear suspension was introduced last year as “PCX,” a name only intended to disguise the rMotion name until the consumer version was introduced. For 2012, the rear suspension is named rMotion Racing. Both skid frames share the same basic geometry with a rising-rate rear shock and long front arm. Each are optimized for their intended uses. The rMotion Racing has a new reinforced rear arm, improved coupling system and new reinforced powder coated rails for reduced ice build up.
Other highlights from the news were significant effort on chassis calibration for less rider fatigue, and minor drivetrain changes for improved belt and clutch performance while racing. Engine mounts were also made stiffer to better align the clutches while on the gas.