ENGINE
The 350cc 4-stroke engine with a state-of-the-art electronic fuel injection offers a very wide power band and is distinguished by a dynamic but fatigue proof power delivery. At over 45hp of maximum power, the 350 XCF-W is strong enough to beat any 450.
GENERATOR
The 350 engine is equipped with a 196W generator with integrated starter freewheel. The generator provides sufficient energy for the fuel injection, lighting and other electrical loads. Compared to the 350 SX-F, the oil-cooled rotor has a bigger diameter with a larger flywheel mass and requires a larger ignition cover.
OIL CIRCUIT
The 350 engine is equipped with two oil pumps. A pressure pump provides reliable lubrication for the crankshaft, piston, counter balance shaft and valve train, while cooling the ignition and lubricating the clutch. A scavenger pump draws oil from the crankcase to lubricate the transmission. This also creates a small vacuum within the crankcase, which increases engine performance. For MY 2015, the oil pump suction screen has new O-rings that increase durability under extreme conditions and over time.
CRANKSHAFT
Compared to the 350 SX-F, the 350 XCF-W has a heavier crankshaft in order to achieve a more even power delivery and better traction through the greater gyrating mass. The crankshaft employs a plain big end bearing. Two force-fitted bearing shells run directly on the crank pin. The necessary oil feed for this bearing is delivered by the engine’s pressure lubrication. This design increases the engine’s long-term durability, lengthening crankshaft service intervals – a customer benefit in terms of time, effort and cost.
BALANCER SHAFT
In order to balance the mass-forces, the 350 XCF-W engine has a counter balancer shaft on the right side, doubling as a water pump drive and cam chain drive wheel. This solution is a major contribution to the extremely compact engine layout.
DDS CLUTCH
The single-piece basket of the DDS clutch (damped diaphragm steel) is machined from solid high-tensile steel in one piece together with the primary drive gear. This process provides unbeatable reliability and contributes to the narrow engine width due to its compact rivet-less design. This construction also allows the use of thin steel linings that contribute to the compact clutch dimensions. The diaphragm spring makes it possible to implement an additional rubber damping system inside the clutch hub, which offers the certainty of reliability for the transmission and good traction. For MY 2015, the clutch basket has been reworked, making it lighter. To compliment the diaphragm spring the Brembo hydraulic clutch mechanism offers a very light operation and good, controllable modulation of the clutch.
ENGINE MANAGEMENT SYSTEM (EMS)
The Engine Management System by Keihin with electronic fuel injection and a 42mm throttle body ensures a spontaneous response and maximum engine performance.
VALVE TRAIN
The crankshaft drives an intermediate shaft on the side which in turn drives the coolant pump and the two camshafts via the cam chain while at the same time acting as a counter balancer. A hydraulic chain tensioner enesures reliable chain tension to achieve highly precise valve timings.
STARTER
The engine is equipped with a kickstarter as well as an electric starter as standard. Well protected behind the cylinder, the electric starter is connected to the freewheel on the ignition rotor via the starter drive in the ignition cover.
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