KTM 300 EXC TPI 2018

Engine & Exhaust

When it comes to optimal power-to-weight ratio and outstanding Enduro specific performance the new KTM 300 EXC TPI engine reigns supreme. It features an all-new TPI electronic fuel injection, which will set a new benchmark in the offroad competition 2-stroke segment. And thanks to its modern architecture including high-end features such as the well protected E-starter, a new cylinder with two injectors and power valve, a 6-speed Enduro transmission and a hydraulically operated DDS clutch, the KTM 300 EXC TPI machine will the best choice when the going gets real tough.

Engine & Exhaust
Cylinder head

The new KTM 300 EXC TPI cylinder has a bore of 72mm and is fitted with the sophisticated power valve, which provides really smooth and controllable power characteristics. For the EFI application the new 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 reduced for less 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. Which is nice if you care about sweet handling. 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 smart surface structure that reduce the wear caused by the rider’s boots.

Transmission

This 6-speed Enduro transmission features an Enduro-specific wide-ratio specification and provides precise and easy shifting. Keeping safety in mind, an advanced ´No Dirt´ gear shift lever design prevents muck 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 new control unit located below the seat. The control unit determines the ignition timing and the amount of fuel to inject is based on several sensor readings such as intake and ambient air pressure, throttle position, oil and water temperature. Thanks to altitude and temperature compensation the rider does not need to worry about fiddling around with the jetting anymore.

Cylinder and piston

Inside the cylinder, with a bore of 78mm, thumps a reliable box-type piston made by CP. Its crown geometry is adapted perfectly to the high-compression combustion chamber (12.8:1), where its rigid structure and low weight maximize performance. Thanks to low oscillating masses, the engine revs freely with plenty of power.

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, bigger smiles.

Clutch

The KTM 300 EXC TPI employs the KTM-developed DDS clutch (damped diaphragm steel) with a wear-free steel basket, extremely heat resistant clutch plates and new, 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 EXC 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 previous 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 newly developed throttle body made by Dell`Orto. It features a diameter of 39mm. The airflow is regulated by a butterfly connected with a twin-cable throttle cam, which is operated by a new 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.

Rekluse EXP 3.0 centrifugal force clutch kit

Cooling

Cooling

KTM’s proven cooling system routes the coolant from the cylinder head through the frame triangle, directly to aluminum radiators made by WP. The additional KTM PowerParts radiator fan that riders can add to this fuel injected 2-stroke is now regulated by the control unit, no thermo switch is required anymore. Thanks to flow optimized internal circulation and CFD-calculated ventilation, the system is superbly efficient. In addition, new radiator protections 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.

Radiator fan

Radiator fan

Foam rubber

Radiator protection sleeve

Radiator protection

Exhaust

Exhaust

This nickel-plated pipe is produced by WP Performance Systems. It is taken over from the carburetor model and designed for an optimal power band and maximal performance of the engine. A modern 3D production process guarantees top precision and reliability of the pipe, so this screamer is as tough as it is strong.

FMF Titan Powercore 2.1 silencer

FMF Factory Fatty pipe

FMF Fatty pipe

FMF Powercore 2.1 silencer

FMF Powercore 2.1 silencer

Akrapovič "Slip-on Line"

Factory expansion chamber

Expansion chamber guard

CNC-parts

Oil plug

Factory control cover

Outer clutch cover