Ski-Doo RAS 2 Front Suspension
For 2015 Ski-Doo is introducing a new front suspension called the RAS 2. The RAS 2 (Response Angle Suspension) front suspension has three main benefits: improved straightline precision in big bumps, less roll in corners and lighter weight. All those benefits are found in a more sophisticated styling. The changes bring the RAS 2 up to the level of the rMotion rear suspension and further improve chassis balance.
Geometry-wise, a new forged spindle is 12mm taller, moving the upper ball joint higher by the same amount. This changes the camber throughout travel to minimize bump steer, providing even more precise handling in big bumps. With a minimum camber change throughout the suspension stroke, the skis toe- out the slightest bit when the suspension is fully compressed – so in a big bump, the sled remains stable and tracks true. This will make the sled more predictable and confidence-inspiring in big bump situations.
The new angle of the upper A- arm, created by the taller spindle, also raises the roll center of the sled by 38mm, moving it closer to the center of gravity. While the REV-XP front suspension already cornered very flat, this flattens the cornering attitude even more and further minimizes inside ski lift.
Every component of the front suspension was looked at to reduce unsprung weight for quicker and more controlled suspension response. Refinements in materials and design resulted in notable reductions. The new A-arms feature revised forgings and thin wall chromoly tubing to save weight. The upper A-arms are 100 grams lighter, that’s almost a quarter of a pound. The lower A-arms are 350 grams lighter, three-quarters of a pound. The ski legs are also lighter by 350 grams, yet another three-quarters of a pound.
The A-arms also make a more direct line from the bulkhead to the ball joint – resulting in an extra 20 mm of ground clearance.
Ski-Doo also worked to add more style to the RAS 2. The upper A-arms use flattened tubes and a structural X-brace. The ski legs are forged, painted and CNC machined to add surface interest and expose parts of the aluminum, now clear-coated for a lasting appearance. It’s the same technology used in high-end automotive wheel
From the Spring 2014 issue of SnowTech Magazine. To see all the great articles from SnowTech you have to be a subscriber to the magazine. Subscribe here – and have SnowTech delivered to your door.
