ASK THE MXPERTS: BUILDING THE FASTEST 250 POSSIBLE

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Niccolo Antonelli is racing this 2017 KTM RC250 Moto3 race bike in the Moto3 series.

Dear MXA,
    Since KTM has the most powerful engine in MotoGP 250cc Moto3 road race championship, what are the odds of them using this engine in their motocross bikes in the future? They would be awesome.

The 250cc KTM road race engine.

When the FIM replaced the old 125cc two-stroke Grand Prix class with the 250cc four-stroke Moto3 class, they banned the use motocross engines as a foundation. The Moto3 engine isn’t designed as an engine as much as it is designed as part of the chassis surrounding it. The engine fits into the bike concept, not the other way around. Since the Moto3 engine has a deep and steep inlet port, the KTM RC250 GP bike has its airbox tucked up and away, which helps the engine get more air to increase top-end power output. The center of gravity for Moto3 is critical for good handling, thus ground clearance is sacrificed compared to a motocross bike. According to KTM, a Moto3 engine is always used between 9000 rpm and 14,000 rpm – the class has a maximum rev limit set by the FIM. A Moto3 road racer is wide open for 70 percent of the time, thus low-end power is not as important as on the motocross engine. There is no chance that this engine will ever be seen in a production motocross bike, but there might be some high-tech secrets in the drive train that could cross-over.

KTM’s 2017 KTM Moto3 machines are being raced by Niccol0 Antonelli and Bo Bendsneyder.

 

Photos: Sebus Romero and H. Mitterbauer