2018 Polaris RMK Assault 800 H.O. 155 2018 Polaris® RMK® Assault® 800 H.O. 155 Cleanfire® Manual 2.6 Series 6 LIGHTEST. STRONGEST. MOST FLICKABLE. The 800 RMK Assault 155 is a backcountry mountain snowmobile built for extreme conditions. The tough-as-nails sled, featuring Walker Evans Needle Shocks, is perfect for dominating cliffs and jumps. Features may include: Patented Raised AXYS® RMK® Chassis The AXYS® RMK® features a patented, raised chassis that increases clearance and reduces drag to keep you on top of the snow. The AXYS RMK chassis, purpose built for mountain riding, allows for improved sidehilling, faster and easier climbing, and instantaneous lift allowing the sled to pop onto the snow faster. The aluminum overstructure is lightweight and durable for all types of riding. Taller spindles increases clearance to reduce drag. Rear Suspension The lightweight, rigid rear suspension design features revised geometry to control pitch. This improves weight transfer, delivering better control and a more compliant ride. The rigid suspension delivers power directly to the snow. Off-trail, riders will notice improved weight transfer while maintaining the approach angle. On-Trail, riders will notice a more compliant and comfortable ride. The rear suspension features a rail design that helps lift the rear skid while driving it forward. Proven 800 Cleanfire® H.O. Engine Developed in conjunction with the AXYS platform, the proven 800 Cleanfire® H.O. Engine delivers +10% increase in power-to-weight ratio and quicker throttle response to generate instantaneous lift. The integrated mounting position optimizes the balance of the chassis. Featuring: Grooved piston for improved durability and engine life, 3-stage electronically-controlled exhaust valves for increased power and responsiveness, Electronic oil pump for reduced throttle effort and improved durability, Thermostat with bypass warms up to operating temperature 40% faster and improves durability, High-efficiency intake and exhaust for improved breathability, which increases power, Exclusive VForce Reeds for more power and improved reed life, Lightweight crankshaft that's more durable, 2.5 lbs lighter and has 25% less inertia 3-Stage Electronically-Controlled Exhaust Valves 3-stage electronically-controlled exhaust valves provide improved running quality, crisper throttle response, smoother idle and improved fuel economy. The active feedback for the exhaust valve position provides more accurate fueling in transient situations. These exhaust valves also improve combustion stability, leading to improved durability and engine life. Electronic Oil Pump Electronic oil pump eliminates power-robbing gear drive – and provides more precise, improved oil delivery for performance and durability as well as a 35% reduction in throttle effort. Requires no adjustments. High-Efficiency Intake and Exhaust Porous intake duct material and high-flow exhaust system create a better breathing engine package for more power.