The automotive world hasn't seen a rotary engine in production since the Mazda RX-8 was axed in 2012. However, the Crighton CR700W is bringing it back in spectacular fashion in a machine billed as the "ultimate track bike."
In fact, the engine claims to have one of the highest specific power outputs of any naturally aspirated engine in the world. The dual-rotor mill displaces just 690cc, but generates 220 horsepower at 10,500 rpm (and 105 lb-ft at 9,500 rpm), which translates to 319 horsepower per liter. By comparison, the company says, most MotoGP race bikes make around 300 hp.
There are many advantages to a rotary engine. For one, it's extremely compact and needs fewer parts than a conventional piston motor, and the one in the Crighton is comprised of just three moving parts. Due to its simplicity, the entire assembly weighs just 53 pounds. Even with its six-speed gearbox attached, the unit comes in at just 95 pounds.
Combined with a Spondon-derived chassis made from 7000-series aluminum alloy and Dymag carbon fiber wheels, the entire CR700W weighs just 285 pounds. Even a Ducati Superleggera V4 tips the scales at 336 pounds, and it beats even the supercharged Kawasaki H2R in power per pound.
Unlike reciprocating piston engines, since rotary engines spin in only one direction they vibrate less and love to be revved at high rpm, making them ideal for racing applications. And as it happens, that makes for an other-worldly exhaust note as well. The Crighton promises both smoothness and sound.
Brian Crighton is no stranger to rotary-powered two-wheelers. The former three-time British 50cc-class champ wasn't just a triumphant rider, but an engineer as well. He developed Norton's early 1980s rotary-engined road bike into race-winning machines which terrorized the British Superbike Championship from 1988-94. Crighton's bikes won the top prize thrice, in the 750cc class in 1989 and in the superbike category in 1990 and 1994.
The sticker starts at £85,000 ($116,130), and buyers will be able to customize their bike by choosing an Ohlins or Bitubo suspension and whether they want their bikes to be street-legal or track-only. Each one will be hand-built in the UK, and Crighton says only 25 CR700Ws will be made. You can inquire at the Crighton website if you are so inclined.