The CR700W engine contains just three moving parts, measures only 340mm in length by 240mm in diameter, and weighs just 24kg. With its bespoke integrated six-speed gearbox and slipper clutch, designed and made by race-winning Nova Transmissions Ltd, the complete unit weighs only 46kg. Each rotor generates 200 degrees of power stroke per revolution and delivers industry-leading performance figures.
The entire twin-rotor rotary engine has been painstakingly designed, manufactured, and tested by Crighton throughout a 12-year partnership with Rotron Power Ltd. The engine’s structural components are cast in high-strength LM24 aluminium alloy and machined in house. All engine wear surfaces are molybdenum and nikasil plated to ensure light weight, low friction, and high wear resistance.
The main eccentric driveshaft is manufactured from a cryogenically stabilised EN36 steel alloy. Unlike any other motorcycle engine before it, the CR700W features an internal cooling channel, spark-eroded into the core of the main rotor bearing journals. These channels are then liquid-cooled via a fully integrated shaft driven coolant pump.
It is engineering developments such as these, coupled with the latest developments in super-wide rotor geometry, that provide the highest volume-to-surface ratio of any rotary engine before, and are at the core of the CR700W’s industry-leading performance figures.
The combustion sealing elements include ultra-low friction, two-piece silicone nitride ceramic apex seals. The ultra-low density and extreme hardness of this exotic material provides the engine sealing elements with close to zero wear characteristics. This combines with Crighton’s racing-winning innovation: the titanium and inconel exhaust ejector system, which utilises the rotary exhaust system to generate a high energy vacuum through the core of the engine. This vacuum accelerates a continuous flow of air through the finned apex of each rotor tip. This unique system is incredibly lightweight, requires zero moving parts, and is outstandingly reliable.