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Crighton Racing CR700W debut! Rotary engine return with more than 200hp!

Updated: Nov 1, 2021


Brian Crighton (left) with Mason Law and the CR700W


Most people with an interest in engineering, motorsport or the automotive sector will assimilate Wankel Rotary engines with Mazda. However many vehicles have used them to varying degrees of success including Suzuki and most notably, Norton Norton's success with the rotary motor was by and large through the inputs of one man who refused to accept the official line given to him by the then bosses at Norton. The story starts with a scrapped police bike languishing in the corner of a workshop where Brian Crighton relentlessly requested to develop the bike in his own time and at his own expense. The outcome was a more than 40% increase taking the engine from 85hp, to 120hp. Numbers that aren't shocking today, but considering this was the mid 1980's and was the result of a single man's efforts it's arguably ground breaking. The decision makers were still unconvinced but a 1987 visit to the MIRA test track in the Midlands and the development bike clocking more than 170mph managed to convince any naysayers.

The consequence of this was Brian launched a factory backed racing team that won multiple races, claimed multiple lap records, won championships and was a crowd favourite. Especially while running the John Player Special livered bikes at road racing events such as the fabled Isle of Man TT. After the Norton bikes were banned from the British championships over engine displacement claims, the rotary engine motorcycles all but died apart from within Brian's mind. There was unfinished business and after securing a position with rotary engine manufacturers, Rotron Power Ltd, he was once again able to develop a motorcycle. Though this time, it was a bespoke machine for no championship and therefore, has not been constrained by any rulebooks.

Brian Crighton with one of his Norton racers after winning (something which came often)


The Crighton CR700W has been a combined effort with over a decades worth of development and as Brian, now 73, says, “In so many ways the CR700W is the culmination of my career’s achievements. Developed with my excellent lead engineer, Shamoon Qurashi, it encapsulates the absolute best of my engineering wisdom. And I believe the result is the ultimate track and racing motorcycle.” The bike is an incredible feat of engineering and the specification speaks for itself. The headline figures are;

Power

220hp (@10,500rpm)

Torque

142nm (@9,500rpm)

Dry weight

129.5kg

Engine displacement

690cc

Wheelbase

1374mm

Seat height

810mm

What this means is that the CR700W has an effective power to weight ratio of approximately (based on a wet weight estimate of 150kg) of more than 1400hp/ton! That puts it in the realm of MotoGP motorcycles and is more than double that of Kawasaki's H2R. Rotary engines can produce power unlike conventional piston engines due to the fact there is less moving parts and the fact the moving parts are constantly rotating meaning there is a power stroke every 200degrees of shaft rotation (per rotor), it is reported that the rotary motorcycles have no real "power band" as such due to the linear way in which they build their power. The bike isn't purely an almighty engine, the whole package has been painstakingly designed with details such as; a Spondon derived chassis and swingarm manufactured from 7000 series aluminium, Dymag carbon fibre wheels, Bitubo suspension and steering damper (with an option for Öhlins), top spec Brembo brakes and an Inconel ejector exhaust system. The ejector exhaust system helps cool the engine by using the energy created from the exhaust to create a vacuum to pull cool air through the engine. The system helps combat one of the Rotary engine weaknesses which is a production of excess heat.


A computer render of the Spondon derived chassis & swingarm


There will sadly be just 25 CR700W's built so it's unlikely many of us will get to see one, let alone ride one and even more so because the price for these hand-built bikes is £85,000 ($116,000) but someone whom has had the opportunity to ride one is the British motorcycle racer currently competing in the British Superbike championship's GP2 series, Mason Law. He is an accomplished rider having won the GP2 championship in 2020 and took 17 podiums including 6 wins in the 2021 title challenge. He had this to say following his ride Riding the Crighton is a phenomenal experience. The raw speed of the motorcycle is mind-blowing.

‍It feels like being propelled down the runway of an aircraft carrier in a F-35 fighter jet. This raw speed, coupled with its low weight, means it has the power-to-weight ratio of a modern Moto-GP motorcycle but with buckets more torque.”


The CR700W is the combination of function and form

What is clear then, is the CR700 isn't a show pony and whilst it is effortlessly good looking, it has the performance to back it up. Sadly there is no data on noise limits so we're unsure if you'd even have the opportunity to run one at any UK tracks but Crighton Racing do offer the ability to have it road registered which would be fabulous to see. For now details are scarce over the availability of the 25 motorcycles and when production will start but I am sure that all 25 will be snapped up by enthusiasts as ultimately, that's where this bike belongs. In the hands of people who can truly appreciate what a bespoke and fantastic motorcycle this is and be a part of motorcycling history.


For more details on the bike please use the following links; https://www.crightonmotorcycles.com/ https://www.facebook.com/CrightonRacing


Click the images in enlarge


All images included in this article are property of Crighton Racing



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