Oddball engines and prototypes

[husaberg]

I've got the initial Cycle World articles about the H2R and the TR750. Jody Nicholas was on staff and riding for Suzuki at the time so he's written the TR article - with riding impressions in Japan. Ivan Wagar i think did the writeup for the H2R and rode it in Japan.

The early flexy flier TR makes interesting comparison to the final one analysed by Jennings in Cycle mag some years later. I have nothing on the later air cooled H2R or the water cooled version.

Let me know next time you're over here and I'll hunt them out - but I want them back !!!

Will do I still have your other stuff in a drawer next to my Computer.
Actually what year and month is it.

[EssexNick]

Any chance they'll be appear in one of your albums Husa?

[husaberg]

Any chance they'll be appear in one of your albums Husa?

Very good
there is already a TR album that has a test of a TR750 from about 76 and a H1 and H2R one
from plus lots of pipe and porting specs Some came from Grumph. Edit I haven't uploaded them..... I must have did that for a reason?
Is it alright to upload them Greg they are the ones you emailed me from Mike?
I topped up the TR one today.
https://www.kiwibiker.co.nz/forums/a...p?albumid=5013
here is the Kawasaki ones
https://www.kiwibiker.co.nz/forums/a...p?albumid=4964

[Grumph]

Mike doesn't seem shy about sharing old information. I'd seen everything there before years earlier anyway. I'm sure he'd do it differently now, LOL.

As your PM file is full, pending a clearout, Magazines....

TR750 Cycle World March 72

H2R Cycle World February 72

Also found Cycle May 74 The kawasaki H2R an inside look by Cameron. Article mainly on H1/H2 differences.

[EssexNick]

Many thanks

[husaberg]

Paul Hallem one of the guys behind the Hunwick Hallam
Designed this I cant say I actually understand it as I cant see how its exhausted?

After leaving HH Paul designed the Ecoforce EcoH horizontally-opposed twin, a fuel-injected four-stroke that used crankcase induction like a two-stroke. Crankcase pressure forced the mixture into the cylinder through a sidevalve head, harnessing the considerable pumping forces of the reciprocating internals to create an integrated supercharging effect. Gas-charged pneumatic valve control used a conventional camshaft to open the valves but closed them via pressure bled off the combustion chamber that was directly proportioned to engine speed in an attempt to remove some of the efficiency-robbing resistance of conventional springs. By their nature valve springs apply heavier resistance than necessary at lower engine speeds, as the spring rate is fixed and determined by the force needed to close the valves at the maximum engine speed. By eliminating this resistance, the EcoH exhibited better thermal efficiency and lower emissions while remaining simpler than traditional four-strokes, despite using a supposedly obsolete sidevalve cylinder head. The Ecoforce engine achieved some notoriety for its interesting mix of old and new technology applied in a unique fashion, and the claims of power and efficiency offered by the design appeared promising, but the engine ultimately never progressed beyond the prototype stage where a 86x68mm 790cc version produced 80 HP and 80 LB/FT of torque with a 8:1 compression ratio.

[pete376403]

Here's one for someone who has a stack of 70's Cycle magazines (and the time to go through them). There was a column (pretty sure it was "The Downhill Straight" by Michael Shuter). One of the columns featured a "British World Beater" engine design and there was a highly detailed line drawing with it. The engine was a double overhead cam (marketing insisted), pushrod ((easy for the lads in assembly) rocker operated side valves (pre war stock to use up). The article was, of course, tongue-in-cheek.

I'd love to read that again, and see the picture.

[Grumph]

Cycle did do a few spoof type articles - and I remember Shuter's column - but not that one.

One of his best was a talk with an AMA motocross expert at a party. Contract negotiations, brands, tracks all covered, then at the end the expert says with a heavy sigh, "but I've got to walk away - I'm pregnant" It was at the time the AMA allowed their first female pro riders....

[husaberg]

https://web.archive.org/web/20130816...m.au/home.html

[WilDun]

The old SV engine isn't dead yet, Briggs & Stratton have been making virtually the same SV engine for nigh on 80 years (that's what I call a successful engine!), compactness with perhaps lower power and lower cost could still be important for several applications!

Crankcase charged? - good for a better power to weight ratio, it has been tried before and is actually successful in a range of small powerful model aircraft engines, where smoke produced by crankcase charging isn't so important - not so good for the bigger stuff!

I have a drawing somewhere of a small experimental OHV single cylinder engine ( approx 125cc, not model aircraft) from a few years back, which is crankcase charged, but the oil is removed (for reuse) from the fresh charge before it actually enters the combustion area.

Will try to find it and add it to this post.

[Pursang]

Crankcase charged? - good for a better power to weight ratio, it has been tried before and is actually successful in a range of small powerful model aircraft engines, where smoke produced by crankcase charging isn't so important - not so good for the bigger stuff!

How about a diaphragm to separate the wet sump from the intake charge? With 'clever' design it could also incorporate the check valves to control the induction, transfer and compressing the (super) charge, and the seals for the housing. And a blow-off valve for the over run or to maintain constant intake pressure. Only adds One moving part, too.

This would be suitable for a blow-through or direct injection system. Ideally, the Anti-Carburettor (air follows fuel) injection system. (post #29373 in ESE)

We will need lots of simple, efficient, quiet generators for recharging the batteries in E-bikes when you are further than a power cords length from the grid.

Cheers, Daryl.

[WilDun]

How about a diaphragm to separate the wet sump from the intake charge? With 'clever' design it could also incorporate the check valves to control the induction, transfer and compressing the (super) charge, and the seals for the housing. And a blow-off valve for the over run or to maintain constant intake pressure. Only adds One moving part, too.

This would be suitable for a blow-through or direct injection system. Ideally, the Anti-Carburettor (air follows fuel) injection system. (post #29373 in ESE)

We will need lots of simple, efficient, quiet generators for recharging the batteries in E-bikes when you are further than a power cords length from the grid.

Cheers, Daryl.

Yes, I have often thought that you could have a large diaphragm situated on the crankcase side wall, driven by the pulses from the crankcase - - not sure about pumping efficiency though - suck it and see I guess!

I'm sorry, I didn't find the picture I was talking about - I had to go to my son's place to help out with his alpacas - (200Km away), so I haven't had time to have a good look for it, but I'll find it!

As far as I can remember, the idea was that fresh charge leaving the crankcase went through a curved "transfer" pipe and the oil, being the heaviest constituent of the mixture was centrifuged out and returned to an oil tank for reuse - (can't exactly remember the details)
I guess the idea was to have an oil pump drawing from this tank, supplying the right amount to the mixture (as in Suzuki, Yamaha etc).

At the moment, as I see it the electric motor will take over, but in the immediate future the hybrid is probably the best (maybe only) way to go for the two stroke's survival on the roads or maybe even in the air - I don't want to sound pessimistic but the two stroke engine (rightly or wrongly) will be completely left out in the cold, ie unless someone can clean it up and address all it's other inherent problems - that's a pity of course, but that's how it is really!

Unless of course I'm wrong!

[husaberg]

The Norton Commando Triple "Jake"


https://andover-norton.co.uk/en/our-bikes/detail/291

[WilDun]

The Norton Commando Triple "Jake"

Very interesting and to me the Commando was a good machine (except for the vibes and that isolastic frame designed to allow it to vibrate!).
The original design of balancer (with the 2 rods) to my mind would have behaved in a very different way to the Ducati style etc.
The original would have produced straight up and down opposing forces whereas the single rod types would also introduce a turning(oscillating) force to the engine. - It seems that they both worked ok but it would be interesting just to hear someone else's theory.
Then the piston type would be different again! and Hele also did one with a single oscillating link (like the Ducati only earlier).

[Pursang]

The air powered diaphragm pump is an efficient and well proven technology

Here's a couple of pics from my files:




The first one has an extended piston to separate the crankcase from the charge, but why not use a larger diameter for even more boost?

The Shindaiwa is a commercial engine designed for garden equipment, eg Whipper Snippers where a wet sump 4 stroke is not ideal.
4stroke operation on 2stroke petroil. (could also use direct pumped lubrication with all the additional complication).
I've run my 4stroke mower on left over race fuel for years, no significant smoke.

The Ellwood 1300 rotary valve is an interesting bit of work.

cheers, Daryl