58 RWHP Comet 500cc

W

worntorn

VIP MEMBER
Joined
Dec 22, 2006
Messages
8,151
This engine was built by an Australian tuner by name of John Trease. I recently learned that he is also the man who designed the Terry Prince heads I have for the 1360 Egli motor, as yet unassembled. This could get interesting!
The 58 RWHP was acheived with Alcohol fuel. The bike has been raced quite extensively and remains reliable.
Standard 500 comets in good tune are 28 bhp crank, maybe 18-20 rear wheel.
Glen

58 RWHP Comet 500cc
 
If you google that name, come up with the words performance and racing and HDs - and "with his own hand made a 124 inch V-twin motor that puts out 200hp..".

What else is in that motor ? Quite a lump of a piston and similar for the cam, we'd think ?
Didn't John Surtees et al race a Vincent Grey Flash back in those days, it was pretty strong at the time.

A pair of those would make a fairly strong Vincent in its own right,
let alone bumping the capacity up yet another cylinders worth.... !
 
Rohan, this could be more than I bargained for. Honestly, at 348 lbs dry the bike was plenty quick with the 1000cc Shadow tuned engine in there. By the time I got it finished and running the 1360 parts had mostly arrived, too late to turn back.
One concern I had was that all of this Trease/Prince stuff would turn the engine into a high rpm screamer while killing the middle and bottom. I have since learned that these heads make good power at top and huge power in the middle, which is ideal. The power curve is hyperbolic rather than parabolic as many race engines and sportbike engines are.

I also googled John Trease and found that he holds a number of engine design patents. The Ozzies do like to go fast and are very good at it.

Not 100% sure, but I believe the elderly gentleman with the Bushman hat is John Trease. The series A racer is owned by Ian Boyd, who funds the Back in Black race team. He also owns the Comet racer that made the dyno sheet above.

On edit, I watched the vid again and it is clear this is not John Trease. I'll bet he has had a hand in making the atwin go like that!

http://www.youtube.com/watch?v=N5IXx3c8LXc

Glen
 
I don't regard John Trease as an 'elderly gentleman', he is only about 60 years of age. These days like so many others he has cancer, however he still plays motorcycles. I understand his latest effort involves a fast XR750. In the 70s when historic racing started in Australia, he built a 1300cc Harley engine into a featherbed frame, and with Martin Hone (see Mick Hone Suzuki and Rob Phillis) riding it won a lot of Period 3 races against Vincents etc. The bike did not resemble anything which I ever saw raced 'in the era', however 'it could have existed'. Doesn't matter it was fast enough to win and was accepted as 'eligible'. John Trease is a very competent engineer, and made the flywheels for the 880JAP my brother is building, after the original ones cracked. In historic racing, any bike he is involved with usually flies.
 
Rohan, the rider said the guy in the video is Ron Boyd. I've never seen him at a Victorian race meeting. The onboard looks as thought it was taken in Queensland, a long way from John Trease , but our carrier pigeons are effective, I got a real buzz out of watching the on board - how would you be riding that old shit heap making rumblings like that? GOOD STUFF ! ! I will try to get a photo of John Trease and his Harley for you.
 
acotrel said:
Rohan, the rider said the guy in the video is Ron Boyd. .
Click to expand...


Since I said nothing about any video, you are directing your comments to the wrong folks ?
 
Yes, it wasnt Rohan's mistake, it was mine. I first thought the elderly gentleman (80 is elderly) in the vid might be John Trease.
Turns out he is not. And I agree, 60 is not elderly, tho it was when I was 18!
Of interest, the first Irving Vincent, a 1300 which debuted in 2003 and won everything, used Terry Prince Top ends which Trease designed. According to the website, it produced 135 rwhp on alcohol.

Glen
 
There are some people who view the Irving Vincent with disdain. It runs in historic classes however is extremely removed from any original Vincent. My feeling is that there must always be room for anything so beautiful. It is one of the reasons I favour 'classic racing' instead of 'historic racing'. It would be superb to see the Irving Vincent take on the big air cooled ducatis and guzzis. Sadly that will never happen in Australia - we don't have the BOTT.
 
The guys behind the Irving Vincent are Ken Horner and his brother. They have an excellent engineering business in Victoria. John Trease and Terry Prince were involved earlier in developing the castings. I don't believe there are many Vincent bits on the bike.
 
Glen I believe the elderly gentleman you are referring to may actually be Ian Boyd. I've seen him at at the local track with his bikes. He has a quite amazing collection of Vincent's.
Acotrel the Australian championships of the historic racing this year are to be held in Perth. Last time he had a display of ex racing Vinnie's as well as a couple out on the track.
 
Mark, By the time I drove to Perth, I could fly to London and back a couple of times. It is irrelevant anyway, I'm finding it difficult to even afford one practice day at Winton. Is Ian Boyd a WA person? I know I've never seen him at an historic meeting in Eastern Australia. I'd presumed from the video that the circuit was in NSW - was it taken at Wannaroo ? It was certainly a bit stirring - gave me the urge again !
 
Alan, Ian Boyd is a retired cray fisherman who loves racing his old Vincents. He usually has 2 or 3 at the track and at the nationals last time he had a couple more on display. One a Speedway bike and a drag bike (I think. I had some photos but lost them when my computer crashed).
The track in the video could be Collie. It's definitely not Waneroo.
 
Back
Top