Fisher and D-Motor

Fisher Flying Products has been recently awarded the Canadian Dealership for D-Motor engines! The D-Motor engine is a revolutionary engine that uses a Retro design philosophy. Current engine designs almost exclusively utilize an overhead valve arrangement which has been an evolutionary result of the need for increased volumetric efficiency as RPM increases.

This has been driven by the racing industry be it in auto, motorcycle, boat or aircraft racing. More horsepower either needs bigger displacement or higher RPMs. Look at ships. Huge horsepower with low RPM and a resultant huge weight. On the other end, look at motorcycle engines. 5 valves and 12,000rpm equals high HP per Litre.

D-Motor engines are torque motors. Large pistons and short throws. Another term for this is over square. Aircraft engines are limited by maximum propeller RPM. Some where between 2,700 and 3,000 RPM the prop starts to loose efficiency rapidly due to the shock wave being formed as the blade goes transonic.

D-Motor decided that they wanted to make all of their horsepower and torque at an RPM below the transonic speed and they wanted a simple engine that did not have a reduction gearbox. They also wanted this engine to be light. They did this by reducing the complexity and weight of the overhead valve assembly on the head of each cylinder.

This also reduced the width of the engine. It can now fit into cowls that were the exclusive domain of inverted in-line engines like the Ranger, LOM and Gypsy. The engine is fully jacketed for liquid cooling as compared to Rotax which only cools the heads with liquid. This provides a stable temperature environment for the engine which aids in efficient operation.

The engines produced by D-Motor are priced lower than the competition and have a fair warranty that takes care of both parties. They also come in at a lower weight than the main competitor.

Have a look at the engine and specifications at




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