Powerful four-stroke 450cc liquid-cooled four-valve Unicam(R) engine is based on the award-winning CRF(R)450R motocross and CRF450X off-road engines.
Compact, lightweight engine designed specifically for ATV usage is worthy of its CRF heritage.
Unicam valve train provides the light weight of a compact single-cam drive and the optimum combustion chamber shape for maximum power at all engine rpm.
Unicam valve train features a carburized single camshaft that directly actuates two 36mm titanium intake valves. The camshaft exhaust lobe actuates two 30mm steel exhaust valves via a forked, low-friction roller rocker arm.
Electric-start version features an electric starter that drives the clutch side of the crankshaft to provide superior lubrication of starter gears and to produce a narrow engine with a short, strong crankshaft.
Lightweight, compact, internal auto decompressor provides superb cold-starting and hot-starting operation.
Kickstart version incorporates ATV-type forward kickstarting for ease of starting and light weight.
Crankshaft is made of high-strength, low-carbon steel with carburized main journals for maximum durability at sustained high-rpm operation.
Cylinder-head cover is made of magnesium to reduce engine weight.
Forged three-ring 12.0:1 compression slipper piston is lighter than a conventional design, revving quickly while maintaining excellent cylinder sealing and high-rpm power.
Maximum engine rpm is 9850.
Double-carburized connecting rod utilizes a big-end needle bearing for maximum high-rpm performance and durability.
Nikasil cylinder lining is lightweight and provides cooler and quieter operation for extended engine life.
Press-fitted steel spark-plug pipe fits between forked exhaust rocker arms, further contributing to compact cylinder-head design.
40mm Keihin FCR-type carburetor features four rollers on the flat slide, resulting in very light throttle effort, smooth operation, crisp throttle response and excellent rideability.
Carburetor features a throttle position sensor (TPS) that helps maintain linear response throughout the rpm range.
Twin-sump lubrication system separates the oil supply for the crankshaft, piston and valve train from the clutch and transmission. This ensures a cool supply of oil to the clutc
| Other Price Terms: | $ 4,701 USD |