Page 1 of 2

Crighton CR700W

Posted: 31 Oct 2021, 17:45
by Jack
The CR 700W has a 690 cc engine, has a rated power of 220 horsepower and a 105 lb-ft (142 Nm) torque! This means that the CR 700W has a ratio of 319 HP per litre. It's more than an aspirated F1, Ferrari F2004 (309 HP / liter) engine. MotoGP is about 300 HP per litre! Crighton Motorcycles will only hand build 25 units in all, for around $ 116.000.

Image

Image

The CR700W has a dry weight of just 285.5 lbs (129.5 kg),

Re: Crighton CR700W

Posted: 31 Oct 2021, 18:16
by Kwacky
There's talk of a road legal version as well

Re: Crighton CR700W

Posted: 31 Oct 2021, 18:50
by Jack
I did hear that too , nothing officially announced yet though .
If BSB use the same formula Crighton have to compute the cc then I think it would be eligible for the current supersport class , which it would dominate completely , not so sure how it would fare against a full on BSB superbike as it would have a deficit in hp but an advantage in weight , it could be interesting if anyone has the money and a sense of adventure .

Re: Crighton CR700W

Posted: 31 Oct 2021, 18:56
by duke63
220bhp and 129kg dry weight is a mental combination. Looks good too.

Re: Crighton CR700W

Posted: 31 Oct 2021, 19:38
by C00kiemonster
That's ace!

Re: Crighton CR700W

Posted: 31 Oct 2021, 20:05
by Kwacky
Jack wrote: If BSB use the same formula Crighton have to compute the cc then I think it would be eligible for the current supersport class , which it would dominate completely , not so sure how it would fare against a full on BSB superbike as it would have a deficit in hp but an advantage in weight , it could be interesting if anyone has the money and a sense of adventure .
That's one very rich team owner (lol)

Re: Crighton CR700W

Posted: 31 Oct 2021, 20:52
by D41
Jack wrote: If BSB use the same formula Crighton have to compute the cc then I think it would be eligible for the current supersport class ,

Why would the cc need to be computed??
Is it a rotary engine, or something else as equally snazzy....??

Re: Crighton CR700W

Posted: 31 Oct 2021, 21:41
by Stonesie
D41 wrote: Why would the cc need to be computed??
Is it a rotary engine, or something else as equally snazzy....??

Yeah it's a twin rotor Wankel, like the Mazda engine but much smaller.

https://www.crightonmotorcycles.com/" onclick="window.open(this.href);return false;

I'm not saying they can't get it road legal but with current and future emissions standards it would be a hell of an engineering challenge, the RX8 renesis engine has oil injection to keep the seals from eating themselves in no time which makes it a dirty engine for it's capacity and power, good fun to drive though.

Or with it being such a limited production there may be a loophole to make it road legal?

Re: Crighton CR700W

Posted: 31 Oct 2021, 22:54
by Jack
there are apparently a few differing ways to calculate the displacement of a rotary engine , the reason the old Norton rotary didn't compete in MotoGP was that Norton and the governing body used different formulae and were getting a different result on the displacement or so I am led to believe .

Re: Crighton CR700W

Posted: 31 Oct 2021, 23:14
by StMarks
I've got one of ^^ those in that picture... 8)

Almost exactly the same, even the same colour & same black rubber tyres.! (nod)

Re: Crighton CR700W

Posted: 31 Oct 2021, 23:24
by StMarks
The Harris rear stand, that is..

Obviously.!

Re: Crighton CR700W

Posted: 31 Oct 2021, 23:54
by Jack
Stonesie wrote:
D41 wrote: Why would the cc need to be computed??
Is it a rotary engine, or something else as equally snazzy....??

Yeah it's a twin rotor Wankel, like the Mazda engine but much smaller.

https://www.crightonmotorcycles.com/" onclick="window.open(this.href);return false;

I'm not saying they can't get it road legal but with current and future emissions standards it would be a hell of an engineering challenge, the RX8 renesis engine has oil injection to keep the seals from eating themselves in no time which makes it a dirty engine for it's capacity and power, good fun to drive though.

Or with it being such a limited production there may be a loophole to make it road legal?
They have a trick exhaust system that creates a vacuum which draws in fresh cold air to cool the engine and outputs it with the standard exhaust , I'm not sure how emissions are measured but mixing a load of clean air with the exhaust gases prior to measuring emissions must lower the ppm of any particulates .

Re: Crighton CR700W

Posted: 31 Oct 2021, 23:57
by kiwikrasher
While that’s a clever application.. it’s like mixing your 5L of toxic chemicals in a 10L bucket of water prior to throwing it in the lake. The ppm reading is better but the same amount of pollutants are still being produced.

Re: Crighton CR700W

Posted: 01 Nov 2021, 00:21
by Jack
I realised that it was a "cheat" but I think it's more as a result of them wanting to cool the engine more than trying to have one over on the emissions laws and as I said I'm not sure how they go about measuring whatever it is they measure when checking compliance.

Re: Crighton CR700W

Posted: 01 Nov 2021, 10:56
by Monty
duke63 wrote:220bhp and 129kg dry weight is a mental combination. Looks good too.
............. and apparently, no rider aids! Not sure I'd dare to ride that. **** fantastic thing though.

Re: Crighton CR700W

Posted: 01 Nov 2021, 10:58
by Cav
With a good throttle map, surely it'd be really nice to ride? low torque, linear power and probably a really nicely balanced chassis. You don't have to pin it :)

Re: Crighton CR700W

Posted: 01 Nov 2021, 11:14
by Monty
He said one of his aims was to give people the experience of riding a 2 stroke MotoGP bike.


Image


^2 stroke MotoGP bike

Re: Crighton CR700W

Posted: 01 Nov 2021, 11:41
by Cav
They also don't want to kill all their customers. Technology has come a long old way with E-throttles which are infinitely mappable and all sorts of other tech. They could be beautiful to ride.

Re: Crighton CR700W

Posted: 01 Nov 2021, 12:23
by D41
.....At that price they'd better be beautiful to ride.

Re: Crighton CR700W

Posted: 01 Nov 2021, 16:51
by Jack
Cav wrote:With a good throttle map, surely it'd be really nice to ride? low torque, linear power and probably a really nicely balanced chassis. You don't have to pin it :)
Is 105 lb - ft low torque ? From a 690cc motor ?
The Ducati V4S is only 91 lb - ft from 1000cc

fwiw I think it'd be a real beast to ride but enormous fun and very satisfying when you got things right but very painful and expensive if you got things wrong .