The CFMoto 500SR’s 500cc four-cylinder engine has been revealed.

Hot on their surprise unveiling of two SR sportbikes last September – a 675cc and a 500cc – CFMoto has filed the patent for the latter’s engine. The 675cc sportbike, on the other hand, uses a three-cylinder engine.

The patent’s drawings show several elements of the powerplant, including the cooling system which is designed to get the engine up to working temperature quickly to lower emissions. It is because the catalytic converter is only truly functions when its elements reach 400-deg Celsius.

The drawings also shows an engine that is fully CFMoto’s own design, and now “inspired” by other 500cc engines. There is no 500cc inline-four in the market these days, anyway.

As such, the company does it the conventional way, such as chain-driven DOHC, with the cam chain located at one end of the crank. The cam lobs act directly on buckets, rather than the current trend of finger followers. Also, there are four individual ignition coils for each spark plug.

The crankshaft follows the 180-degree convention, hence not a “crossplane” or “Big Bang” arrangement.

The gearbox is a conventional six speed item, but the drawings did not show a quickshifter. The engine’s oil sump is offset for exhaust down-pipe routing.

This new CFMoto 500cc four-cylinder engine is expected to produce somewhere in the regions of 80 hp, hence placing in between CFMoto’s 100hp 675SR and 50hp 450SR. It will also rival the Kawasaki Ninja ZX-4RR and Kove 450RR.

The 500cc bike, which should be named the CFMoto 500SR, looks to have the ergonomics of a street-biased sportbike like the Ninja ZX-4RR, such as higher placed handlebars compared to track-going sportbikes. The prototype showed some aerodynamic elements such as the covers underneath the front brake calipers to channel airflow around the bottom fairing.