01. Engine & Exhaust

Engine
The 300 cc 2-stroke engine is known and respected for offering the most powerful 2-stroke performance in its segment. Thanks to state-of-the-art engineering, innovative 2-stroke design and revolutionary TPI fuel injection technology, the powerplant is more refined than ever before. The compact and lightweight 2-stroke is a great choice for all Enduro riders searching for easy-to-ride Enduro performance with the power and torque to conquer the most extreme climbs.


Cylinder
The KTM 300 XC-W TPI cylinder has a bore of 72mm and is fitted with a state-of-the-art power valve, which provides really smooth and controllable power characteristics. For the EFI application the cylinder features two lateral domes that hold the fuel injectors supplying fuel into the rear transfer ports. The downstream injection guarantees excellent atomization of the fuel with the upstreaming air. Thus the loss of unburnt fuel is minimal for fewer emissions, a more efficient combustion and reduced fuel consumption. A little tube in the back of the cylinder is connected with an intake pressure sensor, which supplies pressure data to the control unit.


Crankcases and engine covers
For optimal mass centralization the lightweight die-cast crankcases hold the clutch shaft and the crankshaft in a high position close to the center of gravity for quick handling and a light feel. In addition, it allows the implementation of a balancer shaft. So your ride will be as relaxed as it is rapid. Plus, your new favorite engine will keep looking as fresh as the day you bought it: the engine covers feature a surface structure that reduces the wear caused by the rider’s boots.


Transmission
The robust 6-speed transmission made by PANKL Racing Systems features an Enduro-specific wide-ratio specification and provides precise and easy shifting. An advanced ´No Dirt´ gear shift lever design prevents mud and dirt from blocking the joint. Because even dirt lovers hate mud when it's in the wrong places.


Engine management system
The engine management system (EMS) of the TPI models features a control unit located below the seat. The ECU defines the ignition timing while the amount of fuel to inject is based on several sensor readings such as intake air pressure, throttle position and water temperature plus a new additional ambient air pressure sensor. Thanks to altitude and temperature compensation the rider does not need to worry about fiddling around with the jetting anymore. Should the rider decide to mount a radiator fan from the KTM PowerParts program, it will be controlled directly by the EMS without needing to add an additional thermal switch.


Balancer shaft
Say goodbye to numb feet and hands. This engine design allows the implementation of a lateral balancer shaft in order to keep the vibrations to a minimum. You know what that means: more comfort, less fatigue, more racing.


Clutch
The KTM 300 XC-W TPI employs the KTM-developed DDS clutch (damped diaphragm steel) with a wear-free steel basket, extremely heat resistant clutch plates and nitrated steel liners. This clever design employs a diaphragm spring instead of the usual coil springs, making for considerably easier clutch action. A diaphragm spring also leaves sufficient space for a damping system to be integrated into the clutch hub. The goal is traction, but durability is as well. Light operation and telepathic amounts of control are standard with this hydraulic Brembo actuated clutch.


Oil pump
Pre-mixing 2-stroke fuel is a thing of the past for KTM XC-W TPI owners. An electronic oil pump feeds oil from the oil tank via the throttle body into the engine intake, and ensures a perfect fuel-oil mix in all conditions and engine speeds. The system, which reduces up to 50% of the smoke from the exhaust system over carburettor models, is managed by the control unit based on the engine’s revs and load measured by the TPS (throttle position sensor). The oil capacity of approximately 0.7 liters is enough for 5-6 refills of fuel, giving you more time to ride, less time measuring things out.


Throttle body
The TPI engine is fitted with a 39 mm throttle body made by Dell`Orto. The airflow is regulated by a butterfly connected with a twin-cable throttle cam, which is operated by the handlebar throttle assembly. A throttle position sensor provides airflow data to the control unit, while a bypass screw allows the regulation of the idle speed. The cold start device also opens a bypass supplying more air. Via an oil intake tube oil supplied from the oil pump is mixed with the incoming air to lubricate crankshaft bearings and cylinder/piston etc.

TPI Alternator
To accommodate the power requirements of the engine management system, the TPI models are fitted with a powerful 196 W alternator and a voltage regulator. The same as can be found on the XCF-W 4-stroke models.

Cooling
Maintaining the optimal engine temperature is crucial to ensuring consistent horsepower throughout the ride. The KTM 300 XC-W TPI features radiators which are mounted close to the center of gravity and match the design of the shrouds perfectly, in order to achieve perfect ergonomics. The additional KTM PowerParts radiator fan is regulated by the EMS control unit for easy installation. Thanks to flow optimized internal circulation and CFD-calculated ventilation, the system is superbly efficient. In addition the radiator protectors improve heat dissipation. Especially in the mud. They are also integrated into the front part of the shrouds to protect the radiators in a crash.


Exhaust
When it comes to power delivery and performance, the exhaust plays a key role and packs a punch that is hard to beat. The 250 cc and 300 cc models feature HD exhaust pipes (heavy-duty) made by using an innovative 3D stamping process which produces a ribbed surface finish. This makes the pipe much stronger, with better resistance against rocks, while also helping to reduce noise drastically. The silencer features a compact shape and end cap with internal designs individually developed for each model, while it is mounted using an aluminum mounting bracket. In addition, the exhaust's shape provides slim ergonomics and more ground clearance, while a perforated inner silencer tube works with lighter damping material for efficient and durable noise reduction.
