Oddball engines and prototypes

[Frits Overmars]

https://s3.amazonaws.com/WEBPOSTS/OZ...ust+design.jpg So simple! Like a Comprex, but No moving parts. 180 degree twin. Bleed down pressure transferred to charge side increasing recharge pressure and volume. Lengths and volumes adjusted to ensure no combustion gasses transferred to either cylinder. For a parallel twin just put a U-bend at the centre bleed down point.

Haha, nice find Daryl! This was my design in 1975 for a 180° parallel twin .

[tjbw]

Haha, nice find Daryl! This was my design in 1975 for a 180° parallel twin .

On 20th March I said, in ESE "That's one of the things that amazes me about two strokes, it seems no matter what idea you have, someone's tried it before."

I rest my case

BTW, your design looks similar to something invented by mother nature

[tjbw]

Management refused to race it unless the designer hele could guarantee it would 100% win in its first race meeting.
Someone in NZ was going to make a replica

I'm sure they could have entered local events, and won. However, on the GP circuit, winning against the NSU Rennmax twin, and also the Moto Guzzi, wouldn't have been easy.

[tjbw]

Very interesting machine, Geoff Duke tried it and was very keen to race (who could have been a better rider for it?) but the high handed way in which it was scuppered was just another nail in the coffin for the British motorcycle industry! - none so blind as those who will not see!
Then on the other hand, we don't know the whole story (politics, country trying to recover financially from WW2 and at the same time paying back lend lease money, while Japan and Germany were being being rebuilt by the US, - times were tight, big handicap!

The brilliant Doug Hele ended his working days with British Seagull (now long gone).
Better news, it seems now that Triumph are back at the top again, taking over from Honda as engine suppliers in Moto GP in the Moto 2 class with their triple (700?) .

Doug had quite a CV. Included work on Douglas Dragonfly, Manx Norton, BSA MC1, Triumph Trident T150 triple, Norton Dominator twin, and, according to Wikipedia, he was also involved with the Norton Rotaries when he was in his 70s. He also had to put up with his bosses taking credit for his ideas, now that sounds familiar!

I'm wondering if his MC1 was the first racing bike to use a monoshock rear suspension. Why wasn't it used for subsequent frames. Did it look too much like a rigid back end?

http://www.telegraph.co.uk/motoring/...ul-genius.html

https://en.wikipedia.org/wiki/Doug_Hele

[tjbw]

I think the military one was a "Welbike" (worth a google) & the civilian was a Corgi.

Mine was a home-built minibike with wheel barrow wheels and the engine out of a Malvern Star auto-cycle. (also worth a google)
The tank off the auto-cycle is on the other bike, it's a cut-down Victoria 'Nicky' scooter.

Cheers, Daryl.

Yes, it was Welbike.

I bet you had some fun on your own minibike.

[tjbw]

...

Any engine two or for stroke will find its niche of course but lets not decide to put them in little compartments and specify what they should be used for! (let them find that niche themselves) unlike what H***a and D***A have gone and done for four strokes (eh Frits ).

...

Oh dear, I think I'm having a "senior moment" I can't think what a D***A might be.

[WilDun]

Oh dear, I think I'm having a "senior moment" I can't think what a D***A might be.

Ok I was just being stupid ....DORNA (who run Moto GP.)
Frits happened to say that on another two stroke forum, every time he typed in Honda it came up as H***A - apparently perceived as a dirty word!

DARYL, sorry I looked quickly at your photo and thought that it must have been the Mk1 version of the Welbike with the solid wheels etc.
I guess that must have been a younger you on the bike behind - was it another of your creations?

UPDATE - I see you discussed the last question - sorry.

[tjbw]

Ok I was just being stupid ....DORNA (who run Moto GP.)
Frits happened to say that on another two stroke forum, every time he typed in Honda it came up as H***A - apparently perceived as a dirty word!

...

Thanks Will, D***A is the dirtiest. There should be a rival organisation that promotes clean two strokes.

[husaberg]

I'm sure they could have entered local events, and won. However, on the GP circuit, winning against the NSU Rennmax twin, and also the Moto Guzzi, wouldn't have been easy.

We shall never know, i have a write up that was ib one of the first Classic racer mags Hele siad in hindsight the valve angles and head shape were all wrong.
MV and Gilerra were i think in those classes as well. Not to mention Benelli and Morini.
I have never seen much written about the weight it wouldn't surprise me if it was 50 pounds heavier than a Guzzi
The origional MC1 was drawn up by Hopwood but he buggered it up.

"Hopwood was a very stylish designer, but unfortunately his engines would sometimes not run. Bert's original design for the BSA MC1 racer could not have run, because the chain-driven OHC camshaft would not have been able to open the valves. This is not a minor mistake.

Doug had quite a CV. Included work on Douglas Dragonfly, Manx Norton, BSA MC1, Triumph Trident T150 triple, Norton Dominator twin, and, according to Wikipedia, he was also involved with the Norton Rotaries when he was in his 70s. He also had to put up with his bosses taking credit for his ideas, now that sounds familiar!

I'm wondering if his MC1 was the first racing bike to use a monoshock rear suspension. Why wasn't it used for subsequent frames. Did it look too much like a rigid back end?

http://www.telegraph.co.uk/motoring/...ul-genius.html

https://en.wikipedia.org/wiki/Doug_Hele

I have a write up on Doug somewhare a quiet acheiver who often had to develop others designs A guy who would take the time and talk and listen to anyone in the factory.
Not at all like Edward Turner.
developed the "Daytona" race triumphs ie 500 that percy tate etc raced, the domi racer, modernised the Manx norton,
Did a clever desmo one as well.

Also he had a great vision of a series of bikes all based on a modular 200-250 single right up to a V5.
Most of his career was spent just improving others designs and quicky developing engines like the BSA/Triumph three racers.
I am pretty sure he wanted to do a three 10 years before it actually happened.
He also built the Quadrant a 4 cylinder version of the triumph three in quiet without telling his bosses out of bits lying arround the factory.
,
https://normanhyde.co.uk/triumph-exp...-delivery.html
http://www.telegraph.co.uk/motoring/...ul-genius.html
In the Race chassis thread there is a cantalever frame from about 1928, HRD i think

[tjbw]

.....

In the Race chassis thread theye is a cantalever frame from about 1928, HRD i think

Thanks, found it, the suspension was patented by Phil Vincent, and used on his HRD and Vincent bikes.

http://www.voc.uk.com/net/docs/19.16/19-452-49.pdf

[husaberg]

Thanks, found it, the suspension was patented by Phil Vincent, and used on his HRD and Vincent bikes.

http://www.voc.uk.com/net/docs/19.16/19-452-49.pdf

Also the flying Merkel had it in the board track era.
I posted a pic somewhere?
this will do

[Pursang]

Haha, nice find Daryl! This was my design in 1975 for a 180° parallel twin .

So...with the benefit of 40 years of additional knowledge & experience, how do we deal with one exhaust port closing just as the other opens?

Changing the phasing, or the stroke, might allow one of them to charge the other, but not visa versa. So some extra power, but not double?

Asymmetrical piston motion through linkages has been looked at and rejected for adding too much complication.

That only leaves engines with 3 or more cylinders to provide the pulses.

Old Kwakas and Suzi triples did run OK(ish) with 3 into 1 chambers. Is there more development left here?

[Pursang]

Thanks, found it, the suspension was patented by Phil Vincent, and used on his HRD and Vincent bikes.

http://www.voc.uk.com/net/docs/19.16/19-452-49.pdf

There's always a way around a Patent.


This is the legendary 1929 Brough named "Moby Dick".

Cantilevered rear, Under-slung, braced swingarm,
Multiple linkages, giving variable rate,
High and low speed adjustable dampers.

Fastest, privately owned, road legal, motorcycle in the world, in 1931.

Just STUNNING.

[Pursang]

I bet you had some fun on your own minibike.

Every body had fun on that minibike.
Dozens of kids (and lots of Mums & Aunties) had their first solo motorcycle ride on it.

DARYL I guess that must have been a younger you on the bike behind - was it another of your creations? UPDATE - I see you discussed the last question - sorry.

Yep, that was a sweet, innocent, un-corrupted, younger, Me.

My Dad & I built the Victoria. 50cc 2T, 2 speed gearbox, 16" wheels, front and rear suspension & brakes.
Couldn't afford a Honda SL70, it was a pretty good substitute.
It lost a Lot of weight when I removed all the Cast Aluminium body work, (probably melted down Messerschmitts)
and it actually went pretty well. Even won some local races on it.
A Nicky scooter is probably a highly desirable classic nowadays, but back in 1970 it was unwanted, giveaway junk.
(and not as flash as the one in the picture).



cheers, Daryl

[Grumph]

There's always a way around a Patent.

This is the legendary 1929 Brough named "Moby Dick".

Cantilevered rear, Under-slung, braced swingarm,
Multiple linkages, giving variable rate,
High and low speed adjustable dampers.

Fastest, privately owned, road legal, motorcycle in the world, in 1931.

Just STUNNING.

Bentley and Draper rear suspension - Irving is rather caustic about the stiffness of that "braced" arm....