The crankshaft on the new 250 EXC‑F has 5% more gyrating mass available for achieving optimum traction. Similarly to last season's KTM SX-F models, it is equipped with a plain bearing in the lower conrod eye. The previous needle bearing is replaced with two press-fit bearing shells that run directly on the crankshaft's crank pin. The engine's direct pressure lubrication system ensures the necessary oil supply. This design enhances the durability of the engine, thereby enabling an extension to the service intervals for the crankshaft - a benefit in terms of time and costs.
Thanks to a completely new design of engine case, which is now manufactured in a pressure die-casting process, it has been possible to significantly reduce the wall thicknesses compared with a gravity die-cast case. A new, high-strength, aluminium alloy ensures that the case is resistant to stone impact and other damage.
To counterbalance the inertia forces, the new 250 EXC‑F engine is now also equipped with a balancer shaft that acts as a multi-function shaft, driving timing chain and water pump simultaneously.
The 250 EXC‑F is virtually a guarantor for top places in hard-fought enduro battles – this is substantiated not only by the numerous world titles. For the 2014 model year, KTM engineers have ignited the next evolutionary stage and developed a completely new, state-of-the-art DOHC engine that unites the concentrated engine expertise amassed from motorsport and development. The design of the new generation shares numerous basic components with the successful 350 EXC‑F engine. This results in a perceptible increase in torque, above all in the low to mid rev range (an additional 4 Nm between 6,000 and 7,000 rpm).