Short Stroke 500cc Triumph

acotrel

acotrel

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A few times on this forum, I have mentioned my 500cc 63mm stroke Triumph engined Triton. If you really want to scare yourself, you might think about doing a Monty and Ward Tricati.

en.wikipedia.org

Geoff Monty - Wikipedia

en.wikipedia.org en.wikipedia.org
 
acotrel said:
A few times on this forum, I have mentioned my 500cc 63mm stroke Triumph engined Triton. If you really want to scare yourself, you might think about doing a Monty and Ward Tricati.

en.wikipedia.org

Geoff Monty - Wikipedia

en.wikipedia.org en.wikipedia.org
Click to expand...
I can remember as a kid reading about these monards in an old well thumbed copy of motorcycle mechanics
Very inspiring to me at that time
 
My memory of Monty and Ward goes back to about 1960. I am fairly certain one of their bikes was a unit construction 500 in a 250 Ducati frame. When the stroke gets down to 63mm, the power characteristics can be horrible. Percy Tait on the works 500, actually finished ahead of a 500cc MV in one race. I think it was on Spa - a power circuit ? One thing I found with my 500, was, once it was really going, it seemed to continue going faster but at a slower rate of acceleration. At Phillip Island I found myself to be passing guys at the ends of the straights. It was a bit strange. I think the inlet port size was miles too big for the capacity of the motor.
When Allan Greening raced it at Bathurst he reached the end of Conrod straight going so fast that he was in trouble. He had to choose between going left or right, and either wat, the angle was the same. He chose to go around instead of the escape road. When he got to the top of the mountain the bike bounced him off the guard rail. He broke an arm and a leg.
Very few other guys ever rode my 500. My brother found he could not get around a corner and ran off. On the same day , another more experienced rider did the same thing.
 
A few years ago, I was at the annual swap meet at Bendigo. There was a guy there who was selling a 1973 Tiger 100A for about $3000. It would have been a good starting point because the timing side main bearing would not have been the BSA bush. I don't know if Nova made a decent gearbox for that motor. Building a race bike out of it, would have cost an arm and a leg. - And for what purpose ?
The stroke of motor is 65.5 mm. Which is what the Percy Tate Triumph 500 would have been. But I would guarantee Percy's motor would not have had that bush in the timing side.
The mentality of British motorcycle manufacturers was very self-limiting. They obviously had to make money, but being mean is not smart. The Japanese gave everyone a much better deal.
Phil Irving was involved in making Velocettes and Vincents. On those bikes, every component is a special. So you are always in the hands of the dealers.
 
I will try & take a few photos for you Al!
I have a Geoff Monty engine a full 650. I dont know how many of the short stroke cranks got made & there is only one of Geoffs mechanics who worked with him at the time thats still around to ask. My mate who I got the engine from (it includes Geoffs own cams) worked with him later. I also have a short stroke 8 valve barrel without a liner in it from his old stock. He ran his engines with rubber mounted carbs to stop frothing before the factory did. Dave Degans was blindingly fast with this engine. Last time I spoke to him many years ago he had a bronze skull in the head from drag racer/sprinter ? (The name wont come) Pip Hingham?
I also have a Dudley Ward big valve head. Huge valves, very big inlets, big bowls around the valve.
They had loads of wins & Dave won everything in classic racing. Once dicing with a couple of Rob Norths at West Raynham, the magazine said they were timed at 145mph!
 
Chris said:
I will try & take a few photos for you Al!
I have a Geoff Monty engine a full 650. I dont know how many of the short stroke cranks got made & there is only one of Geoffs mechanics who worked with him at the time thats still around to ask. My mate who I got the engine from (it includes Geoffs own cams) worked with him later. I also have a short stroke 8 valve barrel without a liner in it from his old stock. He ran his engines with rubber mounted carbs to stop frothing before the factory did. Dave Degans was blindingly fast with this engine. Last time I spoke to him many years ago he had a bronze skull in the head from drag racer/sprinter ? (The name wont come) Pip Hingham?
I also have a Dudley Ward big valve head. Huge valves, very big inlets, big bowls around the valve.
They had loads of wins & Dave won everything in classic racing. Once dicing with a couple of Rob Norths at West Raynham, the magazine said they were timed at 145mph!
Click to expand...
I think the skull man was Pete Davis.

Although Nigel Hall-Smith also did one for me.

I rode Dave’s short stroke 500 8 valve and would easily believe the 145mph. In fact I’d say it would do more if actually built for pure max speed. I had a very fast 840cc Dresda at the time and his 500 8 valve was faster.

The thing was (is) so highly developed in many areas. It revved to 12,000rpm.

I built a 500cc Nourish engined bike some time later and was utterly amazed. It was nothing like Dave’s creation. It felt like a freakin Transit van in comparison !
 
Al did I tell you about my Daytona engines? Nice bike to ride. One engine has an early Quaife 5 speed box it had a really good engine Axtell cams lightened valve gear & cam timing wheels etc, Basset Down balanced crank, High compression pistons.
Second engine has a later 5 speed Quaife with needle roller high gear bearing. Dave Degans engine, offset pins in the rocker arms bath tubbed cylinder head. Dave wasnt pleased I had it lol.
Only spoken to Fast Eddie the season before I brought this from him.
I even had a Dresda Daytona frame to put it in!
Fitted a Robinson four leading shoe drum brake on it. This time Eddie agrees with you! Lol looks great but isnt lol.
 
Eres Accey boy at baffurst .



Not sure thyre as proficent at bending em as the current mob ,


Vrom Vrom . eightyone , Onbored .


 
And ow big ARE these PORTS . Its all very well saying theyre Two Big . HOW Big , ?

Wot r.p.m.'s it pull . Wotsits POWERBAND from'n to . AND wottle she do - Top End .
Ona da flat . Faired or bear .
 
Chris said:
Al did I tell you about my Daytona engines? Nice bike to ride. One engine has an early Quaife 5 speed box it had a really good engine Axtell cams lightened valve gear & cam timing wheels etc, Basset Down balanced crank, High compression pistons.
Second engine has a later 5 speed Quaife with needle roller high gear bearing. Dave Degans engine, offset pins in the rocker arms bath tubbed cylinder head. Dave wasnt pleased I had it lol.
Only spoken to Fast Eddie the season before I brought this from him.
I even had a Dresda Daytona frame to put it in!
Fitted a Robinson four leading shoe drum brake on it. This time Eddie agrees with you! Lol looks great but isnt lol.
Click to expand...

I know where there's a complete (unbuilt) daytona race motor, with a brand new 6 speed Quaife box
 
No, I'm not interested in it.... it's a Triumph after all! Obviously not mine

Just putting it out there in case anyone is interested!
 

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