01. Engine & Exhaust
A legend in its own right, the KTM 300 cc 2-stroke engine has long been a favorite when it comes to enduro weaponry. This is largely down to its exceptional power, low-down torque and overall lightweight. Thanks to state-of-the-art engineering, innovative 2-stroke design, this powerplant has become a truly refined unit.
The cylinder on the KTM 300 EXC has a bore of 72 mm and is fitted with a sophisticated power valve, providing ultra-smooth and controllable power characteristics. The cylinder also features a state-of-the-art power valve unit with a refined mechanism for the lateral support exhaust ports. The exhaust port layout increases engine performance, while the upper contour of the exhaust port has been machined to ensure more accurate port timing.
Crankcases and engine covers
The compact engine cases are manufactured using a high pressure die-cast production process which helps with weight reduction, while retaining strength and durability. The design allows for optimal shaft arrangements close to the center of gravity, resulting in ideal mass centralization and easier ride-ability. Plus, the engine covers feature a smart surface structure which reduces wear caused by the rider's boots, keeping them looking as fresh as the day you bought your EXC.
The KTM 300 EXC makes use of a robust 6-speed transmission made by PANKL RACING SYSTEMS. The gears are made of a strong, forged raw material, ensuring the highest durability and reliability level. Another highlight of the KTM 300 EXC transmission is the no-dirt gear shifter. Similar to the footpeg design, it prevents the build-up of dirt and ensures the next gear is always available, no matter what the conditions.
The KTM 300 EXC engine design allows for the implementation of a lateral balancer shaft in order to keep engine vibrations to a minimum. This means riders can focus on the obstacles ahead of them, with out distraction. After all, more comfort equals less fatigue.
The KTM 300 EXC 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 without compromising durability. Light operation and a 'telepathic' level of control come standard with this hydraulic Brembo actuated clutch. Additionally, this model comes with clutch slave cylinder protection.
The KTM 300 EXC engine is fitted with a 38 mm throttle body made by Mikuni. It regulates the airflow via a butterfly connected with a twin-cable throttle cam, which is operated by the handlebar throttle assembly.
In order to accommodate the power requirements of the engine management system, all KTM EXC models are fitted with a powerful 196 W alternator and voltage regulator to ensure all systems are always powered up.
Keeping the engine cool when the going gets tough comes courtesy of a pair of radiators, mounted close to the center of gravity. These make use of CFD technology (Computational Fluid Dynamics) and clever coolant circuit routing, achieving optimum engine temperature for the highest performance, in all conditions. Above all, the delta distributor, integrated into the frame triangle, features a large center tube for highly efficient coolant flow. The radiators also benefit from plastic protection fins that serve as protection from flying rocks and debris, as well as a brace that disperses energy around the radiators in the event of an impact.
There's more to it than 'braaaap!'. The exhaust plays a key role in packing that signature 2-stroke punch. All KTM 300 EXC models feature heavy-duty exhaust headers made using an innovative 3D stamping process that produces a ribbed surface finish. This makes the pipe much stronger, with better impact resistance, while also helping to reduce noise. The silencer features a compact shape and end cap with internal designs individually developed for each model and mounted using an aluminum bracket for strength. In addition, the exhaust's overall shape provides a slim profile resulting in improved ground clearance, while a perforated inner silencer tube uses lightweight damping material for efficient and durable noise reduction.