Oddball engines and prototypes [Archive] - Page 5

Frits Overmars

15th October 2016, 22:00

Here: http://naca.central.cranfield.ac.uk/reports/1947/naca-tm-1131.pdf This is a NACA translation of German pulse jet development which Kaaden's MZ 2T applied for racing power.That paper gives a good impression of typical german thoroughness. I'm glad the nazis didn't win the war but I can't help admiring a number of german achievements.
The research described in the above paper lead to this, the world's first cruise missile:
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Walter Kaaden was only indirectly involved in pulse jet research, and I think we should put his merits into perspective here.
These days Kaaden is regarded by many as the father of two-strokes. But he invented neither the two-stroke nor the expansion exhaust or the disc valve. Neither did the german Daniel Zimmermann who equipped a 125 cc engine with a flat disc and made it faster than the piston-ported works MZ's. The east-german communist party then 'suggested' that he donate his engine to MZ... Disc valves were patented in 1918 by the british Sun company who actually raced their 250 cc disc-valver in the 1921 TT on the Isle of Man.

Kaaden didn't invent the expansion pipe either. In 1951 DKW-engineer Erich Wolf equipped the 125 cc bike of works rider Ewald Kluge with such a device. At the time MZ was using megaphones and it took another 5 years before Kaaden saw the light. The light was rather dim too, because the 158° exhaust timing of the MZ was far too short for a real expansion pipe. Kaaden switched back to megaphones and only in 1960 did he understand that he had to raise his exhaust timing by at least 30°.

Having said this, Kaaden was the man who kept two-stroke spirits alive after DKW withdrew from racing, and he achieved a lot under harsh conditions in the former Deutsche Demokratische Republik.

Hemi Makutu

15th October 2016, 22:18

Quite correct Frits, I have a copy of the 1957 'Automobile Year' book which notes as such - advances in 2T
power development - & also as 'athodyd' based!

Credit due Kaaden though for getting the 'stinkwheel' riders back on 'the top of the box' in G.P.s - & even getting
the likes of Mike Hailwood to throw his leg over one of 'em...

Niels Abildgaard

16th October 2016, 00:28

From memory , his biography states that Kaaden worked on the tailfins of a rocket powered Henschel glide bomb during WW2.
No pulsejet .

Hemi Makutu

17th October 2016, 10:25

Swedish academic technical appraisal of E-TEC 2T DI marine engine.

http://publications.lib.chalmers.se/records/fulltext/149154.pdf

Hemi Makutu

19th October 2016, 16:51

Has he spent too much.. on the white powder?

http://www.bikebound.com/2016/10/17/gatto-nero/

tjbw

19th October 2016, 21:06

Has he spent too much.. on the white powder?

http://www.bikebound.com/2016/10/17/gatto-nero/

I was watching a snowmobile video just yesterday, and thinking what if ..

Didn't expect to see it realised the next day, and it looks good to me.

Hemi Makutu

21st October 2016, 14:52

www.hirth-engines.de/index.php/en/

tjbw

22nd October 2016, 03:48

In 1956 Triumph decided to try a 200cc two stroke twin, to compete against the rumoured Ariel Leader.

The engine had reed valve induction, with a single carb and LONG inlet pipe. The carb is hiding in the chamber just in front of rear mudguard. It has a single alloy casting for the twin cylinder block, with liners. Initially they used a belt for the primary drive, but it was replaced with a chain. The alternator cover for this prototype was made from a saucepan!

It seems they didn't achieve the expected performance, and the project was abandoned.

They did try different inlet lengths, but I wonder if better performance would have been achieved with 2 carbs on short inlets.

The bike is now on display at the Sammy Miller museum in England.

More photos (showing the saucepan) and text here:
https://books.google.co.uk/books?id=kgwAYJQLRw8C&pg=PA67&lpg=PA67&dq=triumph+200cc+two+stroke+prototype&source=bl&ots=Rv9QRkii3u&sig=6bkxh8IenV93cywluJhAzMMO9c4&hl=en&sa=X&ved=0ahUKEwj1-snQjOzPAhXIDcAKHW3zDeoQ6AEINjAI#v=onepage&q=triumph%20200cc%20two%20stroke%20prototype&f=false

https://www.flickr.com/photos/motosanglaises/4992111353/in/photostream/

tjbw

22nd October 2016, 04:04

Hemi Makutu

22nd October 2016, 13:32

http://www.pattakon.com/pattakonPatATeco.htm

tjbw

22nd October 2016, 14:24

http://www.pattakon.com/pattakonPatATeco.htm

Not the same at all.

Manolis has given a lot of thought to engine designs, and has many interesting projects at pattakon.

He could look at the drawing I posted, and within minutes offer a better solution, as could many others here.

Hemi Makutu

22nd October 2016, 14:37

Not the same at all.

Manolis has given a lot of thought to engine designs, and has many interesting projects at pattakon.

He could look at the drawing I posted, and within minutes offer a better solution, as could many others here.

It was meant in jest, since the apparent simplicity of 2Ts does belie the exactitude of making them work well..

Frits Overmars

23rd October 2016, 04:56

It was meant in jest...I guess people still have to get used to the new, improved Hemi :msn-wink:.
Keep up the good work mate.

Hemi Makutu

23rd October 2016, 10:49

I guess people have still got to get used to the new, improved Hemi :msn-wink:.
Keep up the good work mate.

Well rounded or what eh, chippie?

http://cdn.intechopen.com/pdfs-wm/43662.pdf

tjbw

23rd October 2016, 11:47

Well rounded or what eh, chippie?

http://cdn.intechopen.com/pdfs-wm/43662.pdf

Yes, I think of you as hemispherical hemi makatu ;)

Nice link, thanks.

lohring

24th October 2016, 03:04

Well it's the weekend, so some might like to contemplate this drawing.

To be fair the author commented on a revision to this shortly after it was posted, perhaps he should have corrected the drawing too.

If the designer expected to actually increase the power he would need to increase the exhaust back pressure along with the intake pressure. A turbocharger is a better (and widely proven) solution.

Lohring Miller

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tjbw

25th October 2016, 03:49

If the designer expected to actually increase the power he would need to increase the exhaust back pressure along with the intake pressure. A turbocharger is a better (and widely proven) solution.

Lohring Miller

325249

No lag with the supercharger. I'd love to see some of the proven solutions, including more photos and info on the engine in your post. I'm aware that some large two stroke marine engines use poppet exhaust valves with a turbocharger.

Retrofitting a 'charger to an existing 2 stroke engine can result in the additional mixture getting blown out the exhaust port, and would indeed require exhaust redesign to return the additional mixture to the cylinder.

Whilst I'm not convinced that the complication is worthwhile, I'd love to play with one of these:

tjbw

25th October 2016, 05:34

Recently we had a look at a Villiers V4 2 stroke which used a supercharger to send mixture to a shared crankcase.

Here's an old NEC V4 liquid cooled 2 stroke, it was built in 1910. It has a 3 chamber supercharger. Two of the chambers send air direct to the piston controlled transfer ports. The third chamber sends mixture to a cylindrical rotary valve, which then opens after the transfer port. The objective being to purge exhaust gas, from the cylinder, before mixture is transferred via the transfer ports.

Other features include, cast iron cylinders with integral head, cast iron deflector pistons, and copper water jackets.

This engine, which is on display at the Science Museum in London, is thought to be the first supercharged aero engine, and it is featured in Setright's book "Some Unusual Engines"

Some more photos and text here:
http://www.practicalmachinist.com/vb/archive/index.php/t-112596.html

tjbw

25th October 2016, 06:53

Well it's the weekend, so some might like to contemplate this drawing.

To be fair the author commented on a revision to this shortly after it was posted, perhaps he should have corrected the drawing too.

I guess the problem with the drawing I posted was due to the graphics being delegated to someone who didn't fully understand the request, which was to add a breather hole at the top of the transfer port. The hole was added, but the transfer was shaded (closed), so no mixture would ever reach the cylinder. It doesn't help either if the centrifugal supercharger is rotating in the wrong direction.

tjbw

28th October 2016, 12:31

Here's a 13 minute video, uploaded by VisioRacer on youtube, with "14 unconventional engines". Includes 2, 3, 4, 5 and six cylinder engines, and also a Rolls Royce turboshaft engine.

https://www.youtube.com/watch?v=iaCIidQ1Mjs

lohring

29th October 2016, 02:07

No lag with the supercharger. I'd love to see some of the proven solutions, including more photos and info on the engine in your post.

Snowmobiles have run turbochargers like the engine pictured for a long time. Some ran variable vane turbines to reduce lag. The engine pictured developed around 800 hp with nitrous injection. Below are some more pictures.

The most noted supercharged and/or turbocharged two strokes were the Napier Nomad (https://en.wikipedia.org/wiki/Napier_Nomad) and the Rolls Royce Crecy (https://en.wikipedia.org/wiki/Rolls-Royce_Crecy). Single cylinder test engines for the Crecy developed a BMEP of 321 psi with an intake pressure of 36 psi and an exhaust back pressure of 12 psi. Gas turbines were a better solution for aircraft.

Lohring Miller

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Hemi Makutu

29th October 2016, 12:00

These may be of interest to some, the Sabre also being a powerful piston aero-engine, that did see service.

www.hawkertempest.se/index.php/contributions/photos/329-napier-sabre-animations-created-by-sergio-pasquale

Hemi Makutu

1st November 2016, 13:12

https://researchbank.rmit.edu.au/eserv/rmit:161450/Jiang.pdf

Hemi Makutu

1st November 2016, 18:30

The 500cc H1 Kawasaki and the 750cc H2 were the ultimate in unmanageable street bikes, but they did thrill (and kill) us young "tossers" so that was the end of the British bikes.

I bought my 1st H1 as a ride to work commuter, partly because I didn't want wear out my sporty Triumph
doing such mundane miles, & partly because in those days it was too likely to be stolen, if left outside.

I got flak from my Brit-bike mates for going Nippon & 2T, but yet, they had to respect its capabilities..

H1 was not "unmanageable" - at 500cc it had enough low rpm torque to purr about on, even economically,
& with the powerful electronic ignition, not foul plugs either..

They didn't steer nicely like the Brit bikes of the day, for sure - despite Kawasaki changing the angles etc,on
every model change, but stay rubber side up & the ground clearance/roadholding was ok..

The H2 was even more docile, but as shown below, made a good production racer, even in Europe.

www.kawi2strokes.com/forum/viewtopic.php?f=22&t=1350

Frits Overmars

2nd November 2016, 09:20

I stumbled upon this video: https://www.youtube.com/watch?v=SL1uwRtqPWE
Crank phase variaton on the fly - I love it.
I just hope Flettner doesn't see this; I'm afraid he wouldn't be able to resist...

Hemi Makutu

4th November 2016, 14:27

Might make a good basis for a bike mill.. www.recpower.com/3703%20-%203%20cylinder%20-%202%20cycle.htm

Flettner

7th November 2016, 17:33

I stumbled upon this video: https://www.youtube.com/watch?v=SL1uwRtqPWE
Crank phase variaton on the fly - I love it.
I just hope Flettner doesn't see this; I'm afraid he wouldn't be able to resist...

Dangerous! No I'm all projected up. After running this injected F9 Kawasaki so much now, I'm keen to finish the 360 rotary valve project (and the gyro engine, same cylinders).

Niels Abildgaard

7th November 2016, 20:12

Hello Flettner.

Have some harebrained schemes for aircrafts and want to ask:
How much power /prop RPM for a single/twin Gyro and diameter of prop?
My scheme is inspired by this

http://www.pvpkart.com/112%20right%20inside%20with%20crankshaft.jpg

Cylinders closer together,common combustion chamber and a belt from each crankshaft to side by side props.
Very good balance and no vibrations.
Are crazy people still flying belts between engines and props?

tjbw

9th November 2016, 01:07

Snowmobiles have run turbochargers like the engine pictured for a long time. Some ran variable vane turbines to reduce lag. The engine pictured developed around 800 hp with nitrous injection. Below are some more pictures.

The most noted supercharged and/or turbocharged two strokes were the Napier Nomad (https://en.wikipedia.org/wiki/Napier_Nomad) and the Rolls Royce Crecy (https://en.wikipedia.org/wiki/Rolls-Royce_Crecy). Single cylinder test engines for the Crecy developed a BMEP of 321 psi with an intake pressure of 36 psi and an exhaust back pressure of 12 psi. Gas turbines were a better solution for aircraft.

Lohring Miller

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Thanks for the photos, it looks great!

Napier Nomad and Rolls Royce Crecy were both very interesting engines. I also believe that the large turbocharged uniflow 2 stroke marine engines e.g. from Burmeister & Wain are noteworthy.

A 98 page history of marine turbocharged 2 stroke engines can be found here:

http://www.cimac.com/cms/upload/history/Dragsted_History_Booklet_2013.pdf

tjbw

9th November 2016, 01:24

Niels Abildgaard

9th November 2016, 04:04

Hello TJBW

Burmeister&Wain makes me proud to be danish.
Two strokes work better with exhaust valves.
The Ultraligth Trike and Gyro engine powerplant I have in mind is a two cylinder like the PVP thing with a common combustion chamber and an exhaust valve over each piston.
Geared cranks.
From each crank a belt to a prop shaft ca .5 meter away.
Having two props of 1.2 meter diameter one meter apart gives same efficiency as a single of 1.7 meter diameter and has no torque reaction going back on airframe and gets more undisturbed air.
I will try a scheme one.

Better than picture here:

http://www.ultralightnews.com/ppcinfo/images/voyaguer.jpg

Frits Overmars

10th November 2016, 00:37

Cylinders closer together, common combustion chamber.Cylinders closer together would be good. In fact it's what the championship-winning DEA superkart engine has. Below you can see the PVP engine and the DEA engine.
But a common combustion chamber? Don't do it! It may sound like a simplification but its disadvantages will not justify it.
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Niels Abildgaard

10th November 2016, 06:25

Cylinders closer together would be good. In fact it's what the championship-winning DEA superkart engine has. Below you can see the PVP engine and the DEA engine.
But a common combustion chamber? Don't do it! It may sound like a simplification but its disadvantages will not justify it.
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It is important that pressure is equal in both cylinders at ALL times,ignition or not and during combustion.
To bring cylinders closer they can be staggered fore and aft and having exhaust valves make it much easier.

Hemi Makutu

10th November 2016, 18:32

Toyota tried to convert a 4T DOHC 4V six into an externally blown/scavenged 2T..
- but the port/time/area of even their hi-po poppet valve machine was inadequate..

Here is a chart of current big outboard mills, note the DI 2T torque/efficiency advantage.

http://continuouswave.com/whaler/reference/graphics/Ranger2510Bay.png

BRP/Evinrude are to fit an electronic 'power-valve' to the hi-po outboards - at long last..

tjbw

10th November 2016, 22:42

Hemi hemi please post correct link for "a chart of current big outboard mills, note the DI 2T torque/efficiency advantage"

Hemi Makutu

11th November 2016, 11:20

Hemi hemi please post correct link for "a chart of current big outboard mills, note the DI 2T torque/efficiency advantage"

More outboard data tjbw: www.boat-fuel-economy.com/evinrude-outboard-fuel-consumption-us-gallons

& Piero Baldini 2T engines here: www.google.tl/patents/US20120304972

This one is a bit interesting, & while the single cylinder uses an auxiliary pumping piston, the triple
appears to be functioning as an interlinked unitary machine using the 120`firing phase synergistics.

Hemi Makutu

12th November 2016, 14:21

http://www.e-tech.com.my/images/graph5.jpg

Hemi Makutu

17th November 2016, 09:15

http://www.continuouswave.com/forum/viewtopic.php?f=7&t=125

Hemi Makutu

18th November 2016, 16:44

http://www.ar15.com/media/mediaFiles/12631/84874.JPG

Frits Overmars

19th November 2016, 01:47

http://www.ar15.com/media/mediaFiles/12631/84874.JPGI wasn't around at the time but Startrick specializes in Ducatis, so my guess would be: an air-cooled Ducati twin (which would also explain why I wasn't present :D).

Hemi, over 50 companies and tuners are using my dyno hard- and software and not all of them have the good taste to confine themselves to two-strokes :(.

Hemi Makutu

19th November 2016, 13:14

& good guess, but never fear, I think it is actually one of your old mate Leo M's 2T Kawasaki 750/3s..

Here is a Norwegian tuned one running 39mm carbs.. ~120 hp, not too shabby for a primitive old piston port machine..

http://s1240.photobucket.com/user/jyrg72/media/tmx39_zpsvqtr3is6.jpg.html

Frits Overmars

20th November 2016, 00:22

& good guess, but never fear, I think it is actually one of your old mate Leo M's 2T Kawasaki 750/3s.A tuned H2 producing 100 hp @ 9000 rpm in 2013? That doesn't sound like Leo. My street-H2 made about that power @ 7500 rpm 40 years ago.
Couldn't your graph have been from one of Leo's 500 cc triples?

Hemi Makutu

20th November 2016, 12:44

Leo has been hobby developing/racing those basic old-school triples for quite some time, & with good results.

He has dyno'd those new German billet triple heads & confirmed that they are worth a ~10% power increase,
- on both the stock set-up & on power-tuned mills.

Adit: ( Funny thing, although 'husaberg' has apparently lost interest in posting here in "his" thread, & claims to put me on "ignore"..
...never-the-less he has just red-repped me for this post.. - shame on you Glen)...

ken seeber

22nd November 2016, 01:11

Adit: ( Funny thing, although 'husaberg' has apparently lost interest in posting here in "his" thread, & claims to put me on "ignore"..
...never-the-less he has just red-repped me for this post.. - shame on you Glen)...

Hemi,
Not sure what this is all about. Doesn't sound great though. Some time ago there was some Oz dude, was it JAW, JAZ or something like that, who got a bit out of hand by seemingly one-upping everyone. Sort of killed the thing for a bit. It was a shame. Husa is a legendary contributor to the pages I read, namely ESE and Foundry. He, like everyone else I am sure, runs short of time every now and then and therefore can't contribute continuously all the time.
Cheers
Ken

tjbw

22nd November 2016, 01:20

" Husa is a legendary contributor"

Agreed, and husa is also brilliant at finding relevant links, wish I knew how he did it, even though google is my friend too ;)

tjbw

22nd November 2016, 07:37

Posted by Freeze HD on youtube:

https://www.youtube.com/watch?v=MfO9PIuYw0E&spfreload=10

Hemi Makutu

22nd November 2016, 11:38

[QUOTE

Adit: ( Funny thing, although 'husaberg' has apparently lost interest in posting here in "his" thread, & claims to put me on "ignore"..
...never-the-less he has just red-repped me for this post.. - shame on you Glen)...

Hemi,
Not sure what this is all about. Doesn't sound great though. Some time ago there was some Oz dude, was it JAW, JAZ or something like that, who got a bit out of hand by seemingly one-upping everyone. Sort of killed the thing for a bit. It was a shame. Husa is a legendary contributor to the pages I read, namely ESE and Foundry. He, like everyone else I am sure, runs short of time every now and then and therefore can't contribute continuously all the time.
Cheers
Ken[/QUOTE]

Well Ken, I'd have thought that the more interesting posts added - the better.. with no need for a 'dummy spit'..
& just how technical accuracy can be misconstrued as an emotive "one upping" or thread "killing" thing is strange to me..

I know Glen can do a decent post, & over on the bucket tuner thread - I recently openly complimented him,
& indeed green repped him - for the excellent Bimota V-Due update he put up..

But I can also see that he's not "too busy" to have put quite a few needless (& plainly malicious) red-reps on my posts..

Anyhow, this pipe/gas flow design data link belongs here: www.chengfluid.com/flow_conditioner

Adit: Now this very post has received just such a needlessly malignant red-rep from "Husa.. ...a legendary contributor",
so hey - that "legendary" record as a "contributor" is sure looking tainted now, eh you jokers...

Frits Overmars

23rd November 2016, 00:54

he's not "too busy" to have put quite a few needless (& plainly malicious) red-reps on my posts.. so hey - that "legendary" record as a "contributor" is sure looking tainted nowHemi, I think this is a once in a lifetime-opportunity to prove that you're above this.
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Hemi Makutu

23rd November 2016, 17:20

Hemi, I think this is a once in a lifetime-opportunity to prove that you're above this.
326424

Now - its true that I have 'a touch of the tarbrush' - along with some Neanderthal - in my DNA...

Yet it is surely up to Glen to contribute something to this thread - other than sour grape red-repping.

Alright, back on topic....

On another thread, the supposed propensity for hard running 2Ts to 'nip up' ( piston/bore heat seize)
on shutting the throttle after a WFO period was discussed.

I suggested an old safety trick of killing the ignition while holding the throttle WFO ( wound fully open)
would offer both cooling/lube & engine braking too.

While I have habitually done so on air-cooled 2Ts, today being summery warm, I grabbed an RZ 350 LC
out of the back shed & ran it up to full heat soak ( middle of temp gauge range in ~27` ambient),
then tried the WFO on killed ignition trick, on a long steep down hill section.

Although the RZ (with P-Vs shut & reed valve induction) didn't offer much engine braking, I was surprised
at how quickly the temp gauge needle dropped into the cool running zone, ( within seconds) & that it
took several minutes of hardish running to get it back up to the middle mark again.

I may put a thermocouple under the plug washer of the centre cylinder on one of my air-cooled triples & see
what that does too...

Pursang

24th November 2016, 01:41

Bourke Engine
http://bourke-engine.com/vlb/
http://bourke-engine.com/
30-50:1 air ratio engine
One stroke like a gun.
312138
312139

There is another Bourke engine: a HCCI, fuel-injected, two-stroke. Developed 1918-32

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Sealed crankcase, under-cylinder transfer chambers.
Fuel injection to transfers
Three layer bearing at yoke for speed reduction.

326433

326434

From a Hot Rod magazine article (July 1954)

2 cylinder 30ci = 490cc (or 491.612 for Frits)
Weight 38lb = 17.7kg (or 17.6901)
Power 114hp @15,000rpm (imagine if it had decent transfer ports)
Successfully run up to 20,000rpm.

In 1968 Russell Bourke said: The refined scotch yoke solved everything for me. Its geometry is such that the twin pistons remain at T.D.C. longer, long enough for the extremely rapid hydrogen-oxygen combustion process to burn all of the fuel before the down stroke really begins. I use compression ratios up to 24-1, which gives the high pressure and temperature needed to trigger the explosive combustion. When a cylinder fires, its piston acts as a projectile and the entire piston and rod assembly moves. As it moves, kinetic energy is transmitted to the crankshaft.

Initial combustion temperature is higher than poppet valves could stand, but as the piston moves on its down stroke, cylinder volume increases. All the fuel has burned, however, and cylinder walls are not seared with flame. Instead, the expanding gases act just as scientific laws say they should - as a refrigerant. The pressure of still-burning fuel is not suddenly valved out to the atmosphere to make a loud noise. There is no exhaust flame throwing heat energy to waste. My engines exhaust is so cool that a man can hold his hand close to the ports without harm.

The straight-line motion of the pistons eliminates piston slap, there is no valve clatter or gear whine, the exhaust is muted. The hydrogen-oxygen combustion does not produce carbon monoxide. If my engine were in general use we would never hear of monoxide deaths or smog caused by these engines. As the pistons are interconnected the crankshaft never feels their reciprocating forces and counterbalancing is not needed. The action of the yoke is such that 100 percent balance is possible for the crankshaft; it spins as smoothly as a flywheel. You might guess that the engine would shake from piston action but it does not, because the twin piston assembly is free as it can't transmit its reciprocating forces to the body of the engine, and also absorbs those forces within itself. It is simply thrown back and forth, explosion forces reacting against momentum forces so that things are cancelled out, as in a free piston engine, which it is.

The engine burns straight fuel like any four-stroke cycle machine. As can be seen in the drawing, the crankcase is separated from the cylinders. Piston blow-by does not go into the crankcase but is re-circulated via incoming charges. Oil in the crankcase is not contaminated and lasts indefinitely. The cylinders and pistons are lubricated by small oil holes which leave a metered amount of oil between the piston and walls. There is no poor idling or spark plug fouling such as is experienced when oil is mixed with two-cycle fuel. Each piston produces a power stroke on every revolution and as twin pistons are the foundation of the idea, there are two power impulses for every revolution. Any number of twin-piston power units can be bolted to a variety of bases to give power clusters of any desired output.

There is a reason for each and every detail. The engine can stand detonation pressures because there is no connecting rod angularity or crankpin bearings to suffer intolerable shock loads. Pistons have turbulating fins on them to impart tornado action to the incoming charges. This makes unburned charges rush past open exhaust ports without going out through them. Piston skirts are split and preloaded against the cylinder walls so there is heat transfer when the engine first starts. If pistons were a loose fit their heads would overheat from detonation before the rest of the metal expanded enough to dissipate heat into the cylinder walls. Connecting rods are bored out to help dissipate any heat into the crankcase oil, this, along with the coolness of incoming charges under the pistons, keeps the national leather seals from scorching. Slipper-type bearings in the yoke have large area and are made of shock resistant alloy, so they withstand detonation easily.

I have run my engines up to 2,000 hours without noticeable wear. They respond to the throttle without faltering. I have had them reach speeds of over 20,000 rpm without harm and the only apparent speed limitation is in the ability of an ignition system to produce sparks that fast. They run well on cheap fuels such as brown distillate, and as for economy, my little 38 pound 30 cubic inch job gave 76 hp at 10,000 rpm and at an easy 6500 rpm burned only one gallon per hour. The Bourke Cycle engine comes closer than anything else that I am aware of to completely fulfilling the five desirable attributes for an efficient internal combustion engine laid down by the unfettered mind of de Rochas a century ago.

*************
Heaps of details & pics & links to more stuff here:http://www.projectbourke.com/
You can even buy the blueprints & the operating handbook.

Copyright (C) ProjectBourke.Com & Bourke-Engine.Com - All Rights Reserved

Flettner

24th November 2016, 07:43

Pursang

24th November 2016, 11:31

I don't believe it, I bet the bugger shakes. How can it not unless you run at least four banks of these at 180 degrees to each other. Forget all the other stuff but it does have a Ryger style under piston, and HCCI back then! I bet Ryger studied this engine at length.

https://www.youtube.com/watch?v=Vx_G0-9PJIE

This replica doesn't seem to shake too much.
His idea is that it's basically a free piston engine, with the inertia cushioned by the compression/combustion at the end of each stroke.

He doesn't think its a 2 cylinder, two-stroke either.
It's a duel piston, mono-stroke with all functions,( induction, compression, combustion & exhaust) completed twice in one cycle/revolution.

His original prototype was an X4 radial (He was a WW1 aircraft engine instructor)
Later ones were the flat twins, or banked together as flat 4's & 6's.

Got to give him points and respect for some Very Advanced thinking.
(We do stand on (or peak over) the shoulders of Giants)

Cheers, Daryl.

Frits Overmars

24th November 2016, 11:55

This replica doesn't seem to shake too much. His theory is that it's basically a free piston engine, with the inertia cushioned by the compression at the end of each stroke.Sure. And that compression pressure presses alternately against the left-side head and the right-side head. Can you guess the result of that?

It's a duel piston, mono-stroke with all functions,( induction, compression, combustion & exhaust) completed twice in one cycle/revolution.I've never seen a better description of a two-stroke twin :rolleyes:

WilDun

24th November 2016, 13:56

This replica doesn't seem to shake too much.
Got to give him points and respect for some Very Advanced thinking.
(We do stand on (or peak over) the shoulders of Giants)

Cheers, Daryl.

A guy who can design and build his own engine is no 'dummy' for a start and people like Mr Bourke are not likely be given to bullshit -The fact that he had it running at all is a great achievement.
Unfortunately in today's world and after the (extremely interesting) Wankel disaster, no manufacturer would be game to risk trying to start something new and unproven.
Why would manufacturers who are doing well with constant tiny modifications to existing technology and raking in big profits want to dump everything and take on something new anyway? - Case in point, almost everything to do with the internal combustion engine is now based around the four stroke despite it's high cost, complexity, weight and lack of compactness!
After all, we in the motorcycle world know that the manufacturers of these engines even managed to gang up on the already established two stroke market and almost wipe it out, so when they can do this, why should anyone even try?

Guess it's because they love to try and it's as good a reason as any! - that's where the Bucket Boys come in!

Flettner

24th November 2016, 17:08

WilDun

24th November 2016, 17:31

Don't get me wrong, good on the guy and some interesting thinking going on but to say it's balanced (or doesn't shake) can not be accurate. It's kind of like saying my twostroke parallel twin is balanced because the combustion forces bounce the piston back where it came from. My twostroke twin is not balanced and although from a distance it looks ok it's not fun to be around up close -- until I fitted the balance shaft.

No,no, I wasn't criticizing anybody (except the 4 stroke manufacturers), just talking in general about what might have been the reason for it not being fully developed by anyone and I guess it didn't get perfected by Bourke because it didn't come into being at the right time, also probably because Bourke was getting on (age wise) amongst other things but I do acknowledge that the vibration could have been a factor - and BTW a piston attached to a crankshaft is definitely not "free" either, as someone I think suggested!

husaberg

24th November 2016, 19:52

No,no, I wasn't criticizing anybody (except the 4 stroke manufacturers), just talking in general about what might have been the reason for it not being fully developed by anyone and I guess it didn't get perfected by Bourke because it didn't come into being at the right time, also probably because Bourke was getting on (age wise) amongst other things but I do acknowledge that the vibration could have been a factor - and BTW a piston attached to a crankshaft is definitely not "free" either, as someone I think suggested!

Those bourkes were designed for opposed piston design, the dwell appeals to me as it can be very useful in what is the most limiting factor of a 2T engine.
Unfortunalely it dewells in the wrong place
But thats just requires a rethink of the linkage
One car maker i think had it tied up but it didn't pan out.

This bit (below)is what drew me to it.
I don't know how many of the claims about it are true or just hype in regards to its extreme lean burn potential

The use of the Scotch Yoke reduces vibration from the motions of the connecting rod—for example, the peak acceleration in a Scotch yoke is 25% less than the acceleration in a conventional crank and slider arrangement. The piston movement and therefore vibration is sinusoidal so the engine could theoretically be perfectly counterbalanced, unlike a conventional engine which has harmonics in the piston movement courtesy of the lateral movement of the crankpin.
The Scotch Yoke makes the pistons dwell very slightly longer at top dead center, so the fuel burns more completely in a smaller volume.
plus

There was an Aussie crowd doing scotch yoke engines based on Subaru engines.
http://www.autospeed.com/cms/article.html?&title=The-SyTech-Scotch-Yoke-Engine&A=0948

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the thing is though the sleeve engine worked pretty much from the get go with little R&D time.
Go the Fletner sleeve engine

I just seen this

https://www.youtube.com/watch?v=CVVwkbvhecg

Plus this

https://www.youtube.com/watch?v=HhX-8RyP214

Pursang

25th November 2016, 00:02

Sure. And that compression pressure presses alternately against the left-side head and the right-side head. Can you guess the result of that?

I've never seen a better description of a two-stroke twin :rolleyes:

I'm sure Mr. Bourke & Mr. Newton would say: "Can't push a head one way, without pushing the piston back the other way".
It's the Law (3rd Law: Equal & Opposite forces, etc.) Is combustion pressure a factor in determining engine balance?
Bourke spent an awful long time developing his engine, perhaps he got some of it right.
A description by someone who attended a dyno test of a Bourke engine said that it rattled as the tuning & timing was adjusted. Noisy? sure, but No mention of shaking. He also identified an error in the the BSFC claim, due to a gearing issue between the engine & dyno.

The Guy that built the replica says that you must use Bourke's design & rules exactly or it can all turn to poop, very quickly.
In the video you can see the engine & dyno move dramatically when he pulls the starter cord.
If it was a real 'shaker' I would expect it to bounce around a bit as he runs it up to speed. My washing machine does.

Duel piston mono stroke was his description, not mine. He also had a bit of a 'thing' about people confusing strokes & cycles.
In those early years, Mr Scott's was probably the main 2cyl two-stroke of renown.
Bourke's engine had only 2 Moving Parts. Perhaps the description was a means of product differentiation.

I'm not supporting, promoting or attempting to sell anything or anyone. Just discussing an interesting engine.

Bourke built actual working engines, he developed a 400ci engine for AMC, their engineers tried to convert it to a low compression, regular engine, that failed and then discontinued the project.

We watched a video of a working replica, seem strange to discount its operation out of hand.

cheers, Daryl.

Frits Overmars

25th November 2016, 00:15

the peak acceleration in a Scotch yoke is 25% less than the acceleration in a conventional crank and slider arrangement.I'm always sceptical when reading such claims, so I did some comparative calculating with an engine where the con rod length is a conservative twice the stroke size, and an engine with an infinite con rod length, aka a Scotch Yoke geometry.

The piston acceleration extrema in the normal engine were
63000 m/s² in TDC; 38100 m/s² in BDC

For the Scotch Yoke these values were
50600 m/s² in TDC; 50600 m/s² in BDC

So the claim of 25% less peak acceleration for the Scotch Yoke seems about correct:
63000 / 50600 = 1,245

But that is not the whole story. For an optimal comparison with the Scotch Yoke let's look at a normal flat twin with both con rods on the same big end pin.

When one piston is in TDC, the other one is in BDC, so the total force on the big end pin is:
63000 * piston mass + 38100 * piston mass = 101100 * piston mass

For the Scotch Yoke the total force on the big end pin is:
50600 * piston mass + 50600 * piston mass = 101200 * piston mass

This seems to be even a fraction more than the total forces in the normal engine, but that stems from the different acceleration profiles over one crankshaft rotation.
If we integrate the acceleration values per crank degree, the normal engine and the Scotch Yoke show identical total values.

So the claim of 25% less peak acceleration in the Scotch Yoke is correct, but irrelevant.

What is relevant, are the lighter pistons that can be used with the Scotch Yoke, although the slot construction around its big end pin may cancel out this advantage.
In the animation shown above there is only a line contact between the big end bearing and the slot, but that will have insufficient load carrying capacity.
An auxiliary sliding construction in the slot will add both mass and friction, and a roller bearing construction will do away with most of the friction there, but add even more mass.
Summary: the Scotch yoke will prevent friction-causing trust forces acting on the piston skirts, and it offers effective under-piston pumping.

Pursang

25th November 2016, 03:01

- and BTW a piston attached to a crankshaft is definitely not "free" either, as someone I think suggested!

That was Russell Bourke's claim. After much reading & thought, I think the explanation is this.

In operation, the Bourke crankshaft does not (need to) impart any energy to the engine to complete a cycle.

In a regular engine, flywheel inertia is required to push the piston through the non-power parts of the cycle.

In a running Bourke engine, the power stroke of one piston pushes the other one through those parts, the crankshaft is not required.

He claims that the crank just captures energy from the process.

In Burke's words: You might guess that the engine would shake from piston action but it does not, because the twin piston assembly is free as it can't transmit its reciprocating forces to the body of the engine, and also absorbs those forces within itself. It is simply thrown back and forth, explosion forces reacting against momentum forces so that things are cancelled out, as in a free piston engine, which it is.

The Bourke engine has a 'formula' that Must be followed. Perhaps there is a specific combination of dimensions: bore, stroke, combustion volume, mass of Piston Assy, mass of housing etc. that produce the harmony. :hug:

Instead of a crank & scotch yoke, the engine could have a lever & ratchet to capture the energy or a linear generator with coils & magnets producing electricity. i.e. A Free Piston Engine.

Like this:
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Which (sadly) brings my thoughts back to Pit-side Battery Chargers for Electric racing machines.:violin:

Cheers, Daryl

WilDun

25th November 2016, 08:00

In operation, the Bourke crankshaft does not (need to) impart any energy to the engine to complete a cycle.

In a running Bourke engine, the power stroke of one piston pushes the other one through those parts, the crankshaft is not required.

Instead of a crank & scotch yoke, the engine could have a lever & ratchet to capture the energy or a linear generator with coils & magnets producing electricity. i.e. A Free Piston Engine.

Cheers, Daryl

Duh!..... yeah it's all beginning to filter through to me now!:facepalm:

Pursang

25th November 2016, 11:29

In the animation shown above there is only a line contact between the big end bearing and the slot, but that will have insufficient load carrying capacity.

Which bit Frits? The Bearing or the Slot or the single line of contact?

Bourke developed a 3 layer, hydraulic slipper bearing to manage the load and speed of the engine.
description here: 326475

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An actual Bourke yoke assembly is a bit more substantial than the animation.
(As you said, negating any lightweight piston advantage).

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Here's an interesting description of the Bourke crank/yoke process;

"Looks like a crankshaft, functions as a camshaft. A high speed, reverse, roller camshaft".

Careful Buddy...Them's four-strokin' words!!:2guns:

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Cheers, Daryl.

WilDun

25th November 2016, 16:17

In Burke's words: You might guess that the engine would shake from piston action but it does not, because the twin piston assembly is free as it can't transmit its reciprocating forces to the body of the engine, and also absorbs those forces within itself. It is simply thrown back and forth, explosion forces reacting against momentum forces so that things are cancelled out, as in a free piston engine, which it is.
Cheers, Daryl

Not meaning to be a smartass, but I'd hate to see it misfire with no crank - The forces would be transmitted to the body then! Especially if there was a squish gap to maintain!
But then what I am saying is irrelevant really (perhaps I am just being a smartass! :facepalm:}.

Flettner

25th November 2016, 18:02

Hum, but what? has to weigh nothing but turn straight line into rotational, perhaps back to the epicycloid crank. I did order some more 7075 yesterday enough to build two rods (just in case the anodizers bugger it up again)
Need to think of something soon as the cylinder to go on this crank is not too far off being cast. I'd like to have a big cylinder 'cast up' before Christmas.

Grumph

25th November 2016, 20:01

Looking at Bourke's "multi layer" bearing, I have to wonder if he ever owned a Royal Enfield...

husaberg

25th November 2016, 20:21

Looking at Bourke's "multi layer" bearing, I have to wonder if he ever owned a Royal Enfield...

Royal Enfield not very long ago brought Harris Performance.
ie Suzuki superbike team and former Yamaha YZR500 frame makers
RE have a huge push on with the aim of producing some "new Sports bikes" in the Modern Triumph mould.

WilDun

25th November 2016, 20:36

Looking at Bourke's "multi layer" bearing, I have to wonder if he ever owned a Royal Enfield...

Yes Grumph, I think I know what you are thinking of, ie the white metal coated floating bush in the big end as opposed to the usual rollers of the day, I used to own a Model G and those never did give much trouble at least not in a road going bike.

husaberg

25th November 2016, 22:33

Yes Grumph, I think I know what you are thinking of, ie the white metal coated floating bush in the big end as opposed to the usual rollers of the day, I used to own a Model G and those never did give much trouble at least not in a road going bike.

RE would have is said to have used them as they were cheaper than Alloy cadged or not rivotd one piece big end cadges, which were not mass produced at the time.
Triumph (speedtwin)at the time ran its Al Alloy rods directly on the crankpin with no bearing at all.
There are MMC rods that do the same now. Reputed to last a whole MX season as well.
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Pursang

26th November 2016, 00:20

Not meaning to be a smartass, but I'd hate to see it misfire with no crank - The forces would be transmitted to the body then! Especially if there was a squish gap to maintain!
But then what I am saying is irrelevant really (perhaps I am just being a smartass! :facepalm:}.

Someone needs to be as 'Smart as'. :shake:
I really don't understand how it works, that doesn't mean it can't.

I can sort of accept the free piston concept, when the engine has no load.
But, in my (sad, tortured) mind, a loaded over-run would put the crank/yoke/bearing hard against the piston action, allowing forces to be transferred to the case.:bash:

But, then again: Maybe the rate of gas expansion allows the 'following' piston to catch up with the yoke and counteract the 'over-runs' attempt to push on the 'leading' piston through the yoke (or visa versa). Hard to think about, hard to explain, hard to visualise. End result, as long as there are compressions & expansions the piston system remains free......Or not?

And that might apply to misfires too?

Don't know if there is any actual squish, compression ratio is high (up to 24:1) But combustion can start at 90deg. BTDC.
Dwell at top and bottom near 45deg.

It's hard to consider in normal terms.

cheers, Daryl,

Pursang

26th November 2016, 00:49

Hum, but what? has to weigh nothing but turn straight line into rotational.....

Ask and you shall receive.

Not quite nothing, but Very light and in both directions too!

https://mtc.cdn.vine.co/r/videos/245CC00CDB999010192773812224_138115679388656c40305 14.mp4_MY95P92WuWx5RzZ92gWLuZ78LlzzrZWor8q2aOirqbS s1AG.2OWxZaYK6C36DIhN.mp4?versionId=d2dyUCFSf4ppcR w6nyQqg0PSwPuWrY6V

Probably pay to be a bit tougher with the specifications when it comes to your Christmas presents. :yes:

Cheers, Daryl

husaberg

26th November 2016, 16:55

nice little demo

https://www.youtube.com/watch?v=UuTNtg7-Bwg

WilDun

26th November 2016, 17:49

nice little demo

A modified version of that principle has been used in shaping machines for over 100 years, it is a sound design which incorporated a quick return stroke (as seen in Husa's animation above) - the overall length of stroke was also adjustable, by moving the position of the beam pivot up or down. Some I'm told were adjustable by moving the crankpin. - Cool machines, those shapers!

https://www.youtube.com/watch?v=Omsyy-RiaqU

WilDun

6th December 2016, 10:32

I did some comparative calculating with an engine where the con rod length is a conservative twice the stroke size, and an engine with an infinite con rod length, aka a Scotch Yoke geometry.
So the claim of 25% less peak acceleration in the Scotch Yoke is correct, but irrelevant.
Summary: the Scotch yoke will prevent friction-causing trust forces acting on the piston skirts, and it offers effective under-piston pumping.

Frits,
Going back a bit to this post and just taking time to try and digest it all, I was thinking that the Scotch Yoke has been around for a long time and seems to work well in many slow speed applications, but I have not seen it applied successfully in high speed operation, wonder why? I'm sure it has been tried often enough.
It looks to me to a very simple acceptable alternative to the normal crank and conrod, but there must be a major obstacle for it not to have been universally used! (lubrication problems?).
I guess the horizontal, vertical and rotary sliding forces involved all get together to cause high frictional losses, but maybe something else as well - got me stumped!

Frits Overmars

6th December 2016, 22:11

...I was thinking that the Scotch Yoke has been around for a long time and seems to work well in many slow speed applications, but I have not seen it applied successfully in high speed operation, wonder why? I'm sure it has been tried often enough.
It looks to me to a very simple acceptable alternative to the normal crank and conrod, but there must be a major obstacle for it not to have been universally used! (lubrication problems?). I guess the horizontal, vertical and rotary sliding forces involved all get together to cause high frictional losses, but maybe something else as well - got me stumped!The Scotch Yoke may have been around even longer than the now-familiar crank and con rod system; I wouldn't know Will. But I've never seen a Scotch Yoke in an engine yet, and I've been around for some time as well.
I agree that it's a very simple alternative, even simpler than a crank and con rod. But that is in theory. I suppose that the main practical obstacles are as I described: either only a line contact between the big end bearing and the slot, which will have insufficient load carrying capacity, or an auxiliary sliding construction in the slot which will add both mass and friction. I guess we will have to wait for Flettner to build it and hopefully prove me wrong.

WilDun

6th December 2016, 22:25

The Scotch Yoke may have been around even longer than the now-familiar crank and con rod system; I wouldn't know Will. But I've never seen a Scotch Yoke in an engine yet, and I've been around for some time as well.
I guess we will have to wait for Flettner to build it and hopefully prove me wrong.

Yeah I guess he's game to give it a go - the "suck it and see" attitude which can sometimes come up trumps!

Frits Overmars

6th December 2016, 23:58

the "suck it and see" attitude which can sometimes come up trumps!Sometimes the English language scares me. Are you saying there's more than one Trump? :facepalm:

husaberg

7th December 2016, 17:39

Sometimes the English language scares me. Are you saying there's more than one Trump? :facepalm:

Trump card is a winning card in a hand. Not to be compared with the Donald Trump who is a whining cad not playing with a full deck.

WilDun

7th December 2016, 20:01

Sometimes the English language scares me. Are you saying there's more than one Trump? :facepalm:

Yes I was thinking as I was typing if the word 'Trump' would bring up Donald! - as Husa says it's a card game term - (you probably knew that anyway).
The English language is not really a language but a compendium of languages (mainly German, Latin, French Norse etc, plus hundreds of recent additions - nothing to do with England any more! - try reading a manual in Chinese English! or a description of a product on Ebay. - or even make sense of the computer trying to tell you that you are wrong if you don't spell it as in 'American' English.

It's just like the two stroke engine! eg.look at the 'KIWI two stroke', it has branched into all sorts of weird things (all thanks to Bucket Racers).:laugh:

Flettner

8th December 2016, 06:49

Yes, Donald Chump, who would have though. Let's see what he will do, I heard him in an interview talking about wind power. He clearly has no idea.

Grumph

8th December 2016, 07:43

Yes, Donald Chump, who would have though. Let's see what he will do, I heard him in an interview talking about wind power. He clearly has no idea.

While I'm not a fan of his, this seems appropriate....

WilDun

8th December 2016, 09:06

While I'm not a fan of his, this seems appropriate....
Good one :laugh: ........ but give the guy a break, he does know about some things - like bullshit and wind power (using hot air) and now he's talking up two stroke triples! what next? - definitely a visionary!

husaberg

8th December 2016, 16:05

Yes, Donald Chump, who would have though. Let's see what he will do, I heard him in an interview talking about wind power. He clearly has no idea.

They have just sarted on a kite wind farm in Scotland, it actually sounds intersting, when i first heard about it I assumed it was static electricity driven, but it works on a kite more like a wnged parasail moving to power a generator.

http://www.independent.co.uk/environment/kite-power-station-scotland-wind-turbine-plant-electricity-a7348576.html
To be fair though the north of Scotland is bloody windy.

Frits Overmars

9th December 2016, 00:28

They have just started on a kite wind farm in Scotland.Not quite yet Husa. This Oct. 2016 article reads: "One of the world’s first commercial-scale, kite-driven power stations is set to be created near Stranraer in Scotland".
Now let's look at another windy place, the Dutch west coast where dutchman Wubbo Ockels presented his Laddermill, 37 years ago. http://www.drachen.org/article/tapping-high-altitude-wind-%E2%80%98ladder%E2%80%99-kites-viewed-energy-source

Flettner

9th December 2016, 10:33

A friend of mine in the US was developing a rotor system for such a Kite (gyro kite) for some big corporation (with lots of money). Power generation from the spinning rotor system, on real long ropes I guess. Supposed to be top secret so I can't say any more about it. :msn-wink:

tjbw

9th December 2016, 13:18

At first glance I thought that this was a uniflow 2 stroke, with a rotary exhaust valve in the head.

However, I soon realised that it's a 4 stroke, with single overhead camshaft.

I also thought that supercharging could be achieved with the two crankcase compression cycles per power stroke, but I guess it didn't work so well, as it never made production.

Michael Moore just posted these images of this engine on the ESE thread:

Now we can see that it's a four stroke, with reed valve controlled crankcase compression, feeding an inlet poppet valve via another reed valve!

WilDun

9th December 2016, 17:21

Michael Moore just posted these images of this engine on the ESE thread:

Now we can see that it's a four stroke, with reed valve controlled crankcase compression, feeding an inlet poppet valve via another reed valve!

That layout was used successfully in the YS (Japanese) model aircraft engines - this gave them a distinct advantage over your average four stroke in that field! but I guess that in bikes etc. the burning of oil in the fuel would not go down well!

Grumph

9th December 2016, 18:44

That layout was used successfully in the YS (Japanese) model aircraft engines - this gave them a distinct advantage over your average four stroke in that field! but I guess that in bikes etc. the burning of oil in the fuel would not go down well!

That Maico appears to be based on the 490 - which is of course a 2 stroke. A bit of smoke from a motocrosser isn't a problem...I'd be surprised if that layout ever approached the 490's HP figures - torque maybe, but no one I know has ever complained about a 490's lack of that....

Niels Abildgaard

9th December 2016, 19:12

That layout was used successfully in the YS (Japanese) model aircraft engines - this gave them a distinct advantage over your average four stroke in that field! but I guess that in bikes etc. the burning of oil in the fuel would not go down well!

Mr Diesel tried the scheme before 1900.His engine was a single cylinder crosshead type so it was easy to arrange

husaberg

9th December 2016, 20:36

In re alternate charging systems:

Michael Moore just posted these images of this engine on the ESE thread:

Now we can see that it's a four stroke, with reed valve controlled crankcase compression, feeding an inlet poppet valve via another reed valve!

That Maico appears to be based on the 490 - which is of course a 2 stroke. A bit of smoke from a motocrosser isn't a problem...I'd be surprised if that layout ever approached the 490's HP figures - torque maybe, but no one I know has ever complained about a 490's lack of that....
Reminds me of this?
http://www.kiwibiker.co.nz/forums/showthread.php/171300-Oddball-engines-and-prototypes?p=1130803792#post1130803792

Ellwood Hybrid – Single Cylinder Reed Valve Intercooled 4 Stroke Engine
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John Ellwood, who built this engine, says hybrid engines working on this principle began back in 1915. John got the idea to build one back in 1994 and he's been working on the constantly evolving project ever since.

The first Ellwood Hybrid was based on a Godden engine, commonly found in speedway motorcycles, he's also built one with a Jawa engine. The first one was converted in a pretty straightforward manner, as John describes it:

“
A hacksaw, drill and file were enough to slaughter the speedway engine. A bit of rubber pipe, two reed valves from an RD 350, a seal on the crankcase and a carb from a Rotax converted a relic into a Hybrid.

He has both a 500cc version which he says puts out an estimated 50 hp and a 1300cc version doing somewhere around 150 hp. The 1300 is all handcrafted and it's fuel injected and water cooled with 4 crankcase mounted reed valves, a belt driven rotary cross head valve, an intercooler and 15:1 compression.
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Ellwood Hybrid reed valve locations on crankcaseJohn has been racing the 500cc version and plans to race the 1300 in Supermono racing in the U.K. so it must run pretty well. I just think it's an interesting combination of 2 and 4 stroke technology.

John has done a lot of work without the resources of any expensive engine building facilities. I wonder how this would run if really refined and, with the right equipment, it would be much easier to determine how much extra power this setup actually provides. Definitely different.

John adds: "...here in Sweden we're having a flying kilometer race at the end of March, Bonneville Salt Flats style - only we do it on ice. I've entered the black 500 Hybrid, and will put on the laughing gas tube, to get a bit extra boost." I checked out the ice racing website and got a chuckle, there's a note, "Don't bring any salt."
http://thekneeslider.com/ellwood-hybrid-single-cylinder-reed-valve-intercooled-4-stroke-engine/
http://ellwoodhybrid.webs.com/

WilDun

9th December 2016, 21:24

One thing (drawback?) about the single cylinder version is that there has to be a holding chamber with non return valves to store the first pulse.
If it were a twin cylinder, either a boxer twin or a 360 deg parallel twin (both having alternate firing cylinders of course) then no storage chamber with valves is required as there are effectively two under piston pulses combined making one supercharge (so to speak) which will go straight to the inlet valve on whichever cylinder is on the inlet stroke.
So a supercharge is produced on each stroke, feeding each cylinder on alternate strokes. - clear as mud? :rolleyes:

ken seeber

9th December 2016, 22:59

As we know, the concept isn’t new, I think Husqvarna also did it ages ago. The difference here is that old mate routed the mixture thru the cam/valve gear to provide lubrication, whereas, I think, the others used the cam chain to carry the oil up to lubricate the top end, independent of the mixture.
What’s been achieved? Possibly a bit more power than the equivalent 4 stroke, but with the additional complexity of reed valves, an isolated crankcase, presumably a split crank with ball/roller bearings, external ducting & oil in/with the fuel.
I reckon the opposite is the way to go. Only if.

Frits Overmars

10th December 2016, 01:33

What’s been achieved? Possibly a bit more power than the equivalent 4 stroke.You're very kind, sir. I'd rather compare it with the two-stroke engine it was based on, which definitely had a good deal more power.
How shall we call this? Castration by cams and valves?

WilDun

10th December 2016, 09:28

How shall we call this? Castration by cams and valves?

Not really, the opposite in fact! - castration removes the "offending?" parts, this adds to them!

Yow Ling

10th December 2016, 18:26

Not really, the opposite in fact! - castration removes the "offending?" parts, this adds to them!

Castration removes the urge

Frits Overmars

11th December 2016, 07:13

Castration removes the urgeThat's the way I meant it, Yow Ling :D.

Pursang

12th December 2016, 23:11

Complicating a simple concept...or, simplifying a complex one?
Best, and/or worst, of both worlds.

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Needs electronic/hydraulic (computer controlled) valve control, variable exhaust geometry, open mind.
Pressurised intake charge would help too.

Cheers, Daryl.

Pursang

12th December 2016, 23:46

Here is a commercial example of the crankcase supercharging process.
http://www.shindaiwa-tools.co.uk/index.php?id=141

A lot of work to go to if it is only a 'marketing' advantage (though worse things have been done).

Cheers, Daryl

WilDun

15th December 2016, 22:37

Here is a commercial example of the crankcase supercharging process.
A lot of work to go to if it is only a 'marketing' advantage (though worse things have been done).

Cheers, Daryl

Daryl, Don't get the top post! - Is there something missing? or have I become completely befuddled? :confused:
-
UPDATE : yes, definitely confused I think! :rolleyes: - I actually do remember an Italian kart engine ( from memory, AMI or something like that)) which used that principle but don't think it could be switched to four stroke mode (guess half speed camshaft required for four stroke)

Most of the manufacturers have now got four stroke models, I have a 25cc Honda which doesn't use crankcase charging but in order to be able to use it in all positions it has a lube system where the oil is whipped up into a mist in a separate tank and is then circulated through the crankcase by the pumping action of the piston, up through the belt tunnel to the OHC setup, then back down into the tank again.
All very interesting, but I can't see that there is any benefit over a two stroke and it's more complicated - haven't seen much evidence of any of those little fourstrokes dominating the market either!

WristTwister

15th December 2016, 22:46

https://youtu.be/MXW0bx_Ooq4?list=RDrLDgQg6bq7o

ken seeber

16th December 2016, 00:14

Daryl, Don't get the top post! - Is there something missing? or have I become completely befuddled? :confused:

I think that all the manufacturers have now got four stroke models, I have a 25cc Honda which doesn't use crankcase charging but in order to be able to use it in all positions it has a lube system where the oil is whipped up into a mist in a separate tank and is then circulated through the crankcase by the pumping action of the piston, up through the belt tunnel to the OHC setup, then back down into the tank again.
All very interesting, but I can't see that there is any benefit over a two stroke and it's more complicated - haven't seen much evidence of any of those little fourstrokes dominating the market either!

Sadly Will, the thing operates on a 4 stroke cycle (and how dare you for ever buying one....:nya:), and they fundamentally don't have the short circuiting fuel scavenging losses of a 2 stroke. Over your Honda, they require no oil changes, hence disposal. In fact, that is one of the arguments for crank case scavenged 2 strokes, that the oil is disposed in the best possible way, combustion.

Still, some one had better get a move on to get the clean 2 stroke thing going before electricity takes over. It's all nice making more power and listening to the sexual arousal of a developed 2 stroke, working thru EngMod etc , knowing where the RAD is, and hours on the dyno, but if there is no place to run it, then it's all over.

tjbw

16th December 2016, 01:32

https://youtu.be/MXW0bx_Ooq4?list=RDrLDgQg6bq7o

Loved it, haven't heard anything like that for years.

WilDun

16th December 2016, 06:15

Sadly Will, the thing operates on a 4 stroke cycle (and how dare you for ever buying one....:nya:),that is one of the arguments for crank case scavenged 2 strokes, that the oil is disposed in the best possible way, combustion.

Still, some one had better get a move on to get the clean 2 stroke thing going before electricity takes over. ........ if there is no place to run it, then it's all over.

Yes Ken, I'm sorry for having bought one, but that was at a time when I wasn't thinking straight!
What you say though is very true - I firmly believe that electricity will eventually eliminate both types of internal combustion piston engine plus the need for gearboxes ( to a large extent anyway), :eek5: - but let us close our ears and minds to any suggestions of that ever happening with racing two strokes!

And as for the "Turbo Encabulator" - there is probably a niche somewhere for it, but when (if) I finally figure that out, time will have run out for me!:confused:
As for those who have got it sussed then time for them has already run out! :killingme

Pursang

18th December 2016, 00:18

Daryl, Don't get the top post! - Is there something missing? or have I become completely befuddled? :confused:
-
UPDATE : yes, definitely confused I think! :rolleyes: - I actually do remember an Italian kart engine ( from memory, AMI or something like that)) which used that principle but don't think it could be switched to four stroke mode (guess half speed camshaft required for four stroke)

Hi Wildun, sorry for the delayed reply, I've been away for a week.

The Top Post: the Ricardo one, needs a bit of thought and a very open mind.

Its a 4 stroke (poppet valve) engine that can operate as a two stroke.
(Or a two stroke engine, with poppet valves, that can operate on a 4 stroke cycle)

Looking at the diagram, the entire cycle is completed in 2 strokes/One revolution.

It uses a loop type scavenge, but from the O/H valves at the top, not ports at the bottom.
Maybe it could be crankcase scavenged, but I expect would be way, way better, with a forced induction system.
Remember also, as so often explained, it's the exhaust doing the scavenging anyway.
Variable exhaust system geometry would be a plus.

Note the orientation of the inlet tract to assist the scavenging.
I could see this being ideal for a Heron set up, with the combustion chamber in the piston.
(Not withstanding the inherent problems with the Heron approach, it was Very Successfully applied in some cases).

As indicated in the post, computerised control of the valves could optimise the transfer processes at any given rpm,
and allow shifting from 2 to 4 stroke operation when desirable. (Not exactly KISS, but not too bad).

Easy to underestimate the potential, but this is a true innovation, rather than just optimisation of existing processes.

The diagram has been around for a number of years, I don't know what the state of development is,
(the Ricardo Coy. has been around engines for "a Number of Years" too!).

Cheers, Daryl.

WilDun

18th December 2016, 08:10

The Top Post: the Ricardo one, needs a bit of thought and a very open mind.
Its a 4 stroke (poppet valve) engine that can operate as a two stroke.
(Or a two stroke engine, with poppet valves, that can operate on a 4 stroke cycle).

Yes Daryl, I just wasn't looking at it closely enough, (also wasn't wearing my proper glasses) - I have seen something similar to that many years ago (about 50 or so). and I had it sussed out then.
Here in the South Island Richard Pearce (who flew his own homebuilt aircraft said to be in 1903 ) actually invented a similar arrangement for a later contraption he built, this could be changed between 2 and 4 stroke operation and would have been pre first world war too.

I could see this being ideal for a Heron set up, with the combustion chamber in the piston.
(Not withstanding the inherent problems with the Heron approach, it was Very Successfully applied in some cases). .

Not really a fan of the Heron arrangement although I once had a Hillman Avenger car and the Heron head arrangement was used (very successfully) in that, a very good engine. The Avenger was the very best of the cheaper cars of that period.

this is a true innovation, rather than just optimisation of existing processes..
Guess you could say that.

The diagram has been around for a number of years,(the Ricardo Coy. has been around engines for "a Number of Years" too!).
Yes, a lot of years, more than most.

Pursang

19th December 2016, 16:10

Discussing the Ricardo 2/4sight engine with a friend, the question was Why? Why switch from 2 to 4 Stroke?

Best Idea we came up with was this:

Quickly accelerate your vehicle up to speed as a powerful 2 stroke.

Once you get to cruise speed, change over to 4 Stroke operation.

Result: Same engine speed with around Half the Power output. :nya:

Perhaps better BSFC than a severely throttled 2 Stroke.

Cheers, Daryl.

WilDun

19th December 2016, 19:27

Why switch from 2 to 4 Stroke?
Quickly accelerate your vehicle up to speed as a powerful 2 stroke.
Once you get to cruise speed, change over to 4 Stroke operation.
Result: Same engine speed with around Half the Power output.

Or, don't piss around, just buy a Prius or a Camry instead! less hassle! :msn-wink:

Pursang

19th December 2016, 23:38

Or, don't piss around, just buy a Prius or a Camry instead! less hassle! ........:puke:

If we weren't the type of loonies who tend to take the road less travelled (& Do it the Hard Way), we wouldn't be here on this forum.:weird:

cheers, Daryl.

WilDun

20th December 2016, 10:31

If we weren't the type of loonies who tend to take the road less travelled (& Do it the Hard Way), we wouldn't be here on this forum.:weird:cheers, Daryl.

Dead right, there's no harm in living outside the square, in fact I find it very comfortable out there - (I mean here)!
"Loonies" are those who refuse to follow the crowd!
That's according to "sensible" people. like my wife - she actually expects me to keep my workshop tidy - can you believe that! - then of course my garage has a laundry in it as well - I guess not many people would be allowed to have a workshop and a laundry sharing space!

:niceone:

Niels Abildgaard

21st December 2016, 21:16

Some thinking for a HCCI genset here:

http://archive.is/s7gTY

http://chevy57.free.fr/FORUM/junkers_two-stroke_crosshead.gif

Found another version with some other pictures . Enjoy and Mery X-mas

https://web.archive.org/web/20080501215400/http://www.iet.aau.dk/sec2/junkers.htm

WilDun

22nd December 2016, 15:20

Found another version with some other pictures . Enjoy and Mery X-mas

Niels, I am intrigued by the fact that the indexing of the crankshafts can be achieved by permanent magnet machines!

I believe that the very successful British locomotive engine (the Napier Deltic, now superseded by newer designs} was actually developed from the original Junkers.

Just might be a little wary of the "intermeshing props" bet they'd be very noisy! - I remember (in the area where I grew up) the Fairey Gannet anti submarine aircraft (using the Double Mamba turboprop engine) and driving co axial contra rotating props - was the noisest aircraft I have ever heard!

BTW, how did the modifications your Boxford lathe work? - (I was on the Boxford forum and talked to you sometimes) - I have just sold mine, because I just could not put up with the constantly slipping belt, also didn't have enough room in my garage. (mine was the AUD Model).

Have a happy Christmas.

Will.

Niels Abildgaard

22nd December 2016, 19:50

Niels, I am intrigued by the fact that the indexing of the crankshafts can be achieved by permanent magnet machines!

I believe that the very successful British locomotive engine (the Napier Deltic, now superseded by newer designs} was actually developed from the original Junkers.

Just might be a little wary of the "intermeshing props" bet they'd be very noisy! - I remember (in the area where I grew up) the Fairey Gannet anti submarine aircraft (using the Double Mamba turboprop engine) and driving co axial contra rotating props - was the noisest aircraft I have ever heard!

BTW, how did the modifications your Boxford lathe work? - (I was on the Boxford forum and talked to you sometimes) - I have just sold mine, because I just could not put up with the constantly slipping belt, also didn't have enough room in my garage. (mine was the AUD Model).

Have a happy Christmas.

Will.

Hello Will.

My Boxford is well and cutting.It only slips when I forget to disengage back gear after changing of chuks.

http://imgur.com/WvKsXOd

https://www.youtube.com/watch?v=DeFLeNPhqDY

I measured the noise from two props on a stationary rig and it was 3 dB more than sum of the two going alone.So long the blades do not crossover each other noise is not so bad.But it will load the synchronizing and that is not solved yet.

I have heard Deltics live on some norwegian torpedo boats and noise from gears was not pleasant.
But the scheme with AC generators on each crank will be worse(short time) as cranks are displaced 20 degree timewise.A loose connection and really expensive sound.

My AC synchronizing scheme needs almost or totally same crankangle.Maybe one can turn the stator of one generator sligthly and have variale compression within limits.
I do not know.

Regards

Niels

WilDun

24th December 2016, 19:40

Happy Christmas everybody.
From Will.

Pursang

26th December 2016, 00:38

Happy Christmas everybody.
From Will.

.....and from me too!

cheers, Daryl. :drinknsin

husaberg

26th December 2016, 10:22

Very few, however, know that Vincent, after the demise of his motorcycle manufacturing business, addressed what he considered to be the outstanding problems of conventional piston engines in a compact three-cylinder rotary with peripheral valves much like those used in high-performance Wankels. Because he was able to raise only very limited backing for his project, Vincent forced it into being by sheer strength of character. Thanks to the generosity of former racer and Cycle World staffer Jody Nicholas, I was lent some of Vincent’s papers and drawings regarding this project.
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The cylinder block, containing three 54mm-bore radial cylinders and pistons moving through 18mm strokes, revolved within and sealed against the inside surface of a cylindrical outer ring. Passing through the ring were large intake and exhaust ports. Two sparkplugs were also threaded into it. Both two-stroke and four-stroke versions were contemplated. Valving was accomplished in both cases by the sliding of the open outer ends of the 120-degree-spaced cylinders past intake and exhaust ports in the outer ring.
327329

Vincent well knew that attempts to make high power from conventional engines ran up against limited valve area, valve float and mechanical stress. His rotary sought to provide very large ports unobstructed by rpm-limited mechanical valves. He could see no reason, thanks to his complex hydraulic sealing system, why it should not operate at extreme rpm.
This seemed achievable, I suspect, because Wankel prototypes had, not long before, overcome similar sliding-seal problems to run and make useful power. The leakage and smoking of the Vincent rotary probably resulted from heat distortion of the outer ring around its hot exhaust ports.
Sealing surface distortion around the exhaust ports of two-stroke Grand Prix-bike cylinders in the 1990s was overcome only after development of complex cylinder-shaping technologies. Vincent lacked the resources of a major R&D department to sort out his engine’s problems, so, it came to nothing. The prototype and many of his engineering drawings have been preserved.

ken seeber

27th December 2016, 12:09

OK Hooser, seeing you have been recently posting so many articles that I can hardly keep up with, I thought that I’d have a go.
The Vincent thing is really interesting. This must have been around 1970, which was ONLY 46 years ago. So, with that little piece of history trivia, here’s a little bit more of the Vincent concept.

327367 327368 327369 327370

Yep, he would have had sealing and sealing friction issues
Probably the thing that inspired me was the realization of the power of the exhaust pressure depression. I reckon that direct air inlet is the go. Either at the transfer port level or via the head.

327371

Frits’s 24/7 is clearly works and is neat, but for the ones I have seen (any more Frits?) are probably compromised by rule constraints, eg KZ where all the mixture must pass via the crankcase. However, unless exh valves etc are used, we are totally constrained by the limited “tuned” rpm window of the exhaust. Still maybe relevant for constant speed applications like generators for those “clean” electric cars with inbuilt "battery anxiety".

WilDun

28th December 2016, 10:24

Dunno about you guys but I am having trouble with any pics posted (only on this thread) - when I click on them to enlarge, the screen goes dark but the photos won't come up, it would stay like that forever if I didn't click "refresh". It then comes right again when I do that, but still I don't get any enlarged pics.
Can still get the pics from the the forum picture viewer though.

Does anyone else have this problem?

tjbw

28th December 2016, 13:06

Will, no problem with the pics here.

WilDun

28th December 2016, 17:00

Will, no problem with the pics here.

All ok now, either someone has done something, or it was just some sort of glitch on my computer!

husaberg

31st December 2016, 17:07

Talk about oddball
A TZ250 converted to boxer configuration with KX cylinders.
327497327498327499327500327501327502

Grumph

31st December 2016, 20:05

husaberg

31st December 2016, 20:14

I would not like to house that in a frame thank you...
If it's mounted with the cylinders vertical, the lower carb would vacuum the track nicely - but bleeding the cooling syatem would be worse IMO.
I'm assuming it's Dutch ? No insult intended.....

Yip I found it following that plate aluminium frame from the air cooled Yam forum

Very long running project with many tricky parts. Chassis is an unknown aluminium plate chassis just like the well known Harmsen 50 and 80cc racingbike's. The front in an standard Paioli magnesium GP fork but whit dubble anti-dive system. The engine is an modified TZ250 engine which is made to an standing boxer engine. Is was made by STARTWIN in Loenen by the Van der Sarre brothers well known for their special bike and cars over here in Holland. This project is still in its parts collecting stage and hopefully ready in the next 2 years.
https://www.facebook.com/coeno.vanhouten/media_set?set=a.234907596569467.57726.100001506864 493&type=3
https://translate.google.co.nz/translate?hl=en&sl=nl&u=http://forum.limburgracingteam.nl/topic/8131-st250/&prev=search

tjbw

31st December 2016, 22:36

Yip I found it following that plate aluminium frame from the air cooled Yam forum

https://www.facebook.com/coeno.vanhouten/media_set?set=a.234907596569467.57726.100001506864 493&type=3
https://translate.google.co.nz/translate?hl=en&sl=nl&u=http://forum.limburgracingteam.nl/topic/8131-st250/&prev=search

Nice find husa :)

There is also a 4 cylinder air cooled boxer, mounted in frame, on that last link!

husaberg

1st January 2017, 19:46

https://www.youtube.com/watch?v=YzRlga2-Hho

WilDun

2nd January 2017, 10:07

All good ......except that he starts the Spitfire Video with a clip of a Hurricane! :facepalm:
However this problem applied equally to the Hurricane and Spitfire and was largely overcome by flipping the aircraft on it's back before following the Messerschmitt into a dive.

ken seeber

4th January 2017, 11:23

Feel free to not let complexity get in the way of a good (or any) idea:

https://www.youtube.com/watch?v=zVSw8YBNb_U
http://www.infinitiusa.com/now/news-and-events/twin-turbo-v6-engine

Fletto, the world is your oyster :rolleyes:.

husaberg

4th January 2017, 12:33

Ocean1

4th January 2017, 16:09

Feel free to not let complexity get in the way of a good (or any) idea:

https://www.youtube.com/watch?v=zVSw8YBNb_U

Low compression means more power?

I'll have to have a wee think about that...

husaberg

4th January 2017, 16:30

Low compression means more power?

I'll have to have a wee think about that...

Low comp at higher revs means more potential boost pressure is possible for a forced induction engine without the risk of detonation.
Two stokes also benefit from variable compression. As well as variable squish clearances.
google polini powerhead.
https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130633793#post1130633793
https://www.kiwibiker.co.nz/forums/showthread.php/86554-ESE-s-works-engine-tuner?p=1130836924#post1130836924
https://upload.wikimedia.org/wikipedia/commons/thumb/7/7a/PowerHead_Polini.svg/2000px-PowerHead_Polini.svg.png

Pursang

6th January 2017, 00:45

Low compression means more power?

I'll have to have a wee think about that...

WOT & 'full' induction charge needs less 'static' compression.

Cruising with heavily throttled intake, smaller intake charge volume, needs more 'static' compression for efficient burn.

..........and every thing in between.

cheers, Daryl.

husaberg

6th January 2017, 19:06

For Grumph
http://thevintagent.blogspot.co.nz/

Grumph

7th January 2017, 06:11

WilDun

7th January 2017, 06:54

I'd be surprised if that survives. Probably re-engined in period.
Lyster's next step was an 8 valve head for the CB450.
At the time of Colin's death he was working on patterns to recreate the 8V honda heads.

I remember Colin Lyster came to live in NZ, when was that? however I didn't know that he had died - probably through my not being active in the bike scene for a period of about 25 years. - I more or less lost track of bikes after the seventies up till around 2000, (coverage of European stuff and in fact anything outside NZ was really quite poor in the eighties and nineties) also trying to bring up a family and make ends meet etc. took precedence!

husaberg

7th January 2017, 08:11

I'd be surprised if that survives. Probably re-engined in period.
Lyster's next step was an 8 valve head for the CB450 - which was a much better package and easier to do.
The one he did do became the property of the American who paid the bills - he got the patterns too.
At the time of Colin's death he was working on patterns to recreate the 8V honda heads.

Er it was rebuilt in 2016

here is some more other stuff
http://progress-is-fine.blogspot.co.nz/2012/11/lyster-frame.html
http://myclassicmotorcycle.blogspot.co.nz/2011/01/labelle-lyster-triumph-racer.html

The Lyster 500 half an imp was covered in cycleworld july 1968.
327694327695
No i don't have it or have accesss to it. All the cycle world web scans on the net only go back to the mid 70's thus far.

there was a picture of it in a two page spead of odd projects in Classic racer mag from the late 80's or early 90's they likely Wooley wrongly called it a half Cosworth from memory

In the 1970's piper did a 8 valve head for the Honda CB350 twin, as well as the better known 16 valve heads for or the 750 fours
I do have a pic of that somewhere.

Grumph

7th January 2017, 11:47

I remember Colin Lyster came to live in NZ, when was that? however I didn't know that he had died - probably through my not being active in the bike scene for a period of about 25 years. - I more or less lost track of bikes after the seventies up till around 2000, (coverage of European stuff and in fact anything outside NZ was really quite poor in the eighties and nineties) also trying to bring up a family and make ends meet etc. took precedence!

Colin lived in Nelson for some years. I think he came here when his wife - kiwi ballerina Gillian Francis - retired. He was an engineer for hire for a long time , going to europe frequently to sort out prototypes etc. Heavily involved with the Cawthron Institute in nelson too.
Did a lot of freelance design work.
Shortly before his death a batch of the Honda frames - pretty well identical to the Imp one - were made under his supervision. As husa knows, there's one in my shed...

Well, yes i am surprised the Imp survived....I think the original Honda is in a collection in the US somewhere.

husaberg

7th January 2017, 12:23

Colin lived in Nelson for some years. I think he came here when his wife - kiwi ballerina Gillian Francis - retired. He was an engineer for hire for a long time , going to europe frequently to sort out prototypes etc. Heavily involved with the Cawthron Institute in nelson too.
Did a lot of freelance design work.
Shortly before his death a batch of the Honda frames - pretty well identical to the Imp one - were made under his supervision. As husa knows, there's one in my shed...

Well, yes i am surprised the Imp survived....I think the original Honda is in a collection in the US somewhere.

He also made frames for Nortons i have a picture here somewhere. Easier maybe to steal them off mike Moore:msn-wink:
Not sure if they are still kicking around.
As Grumph knows the Patton frames are similar in the dual headstock detail very small tube design.
327696327697327698327699327700

Grumph

7th January 2017, 15:37

The Lyster G50 which won NZ500 titles for 2 different riders still survives in ChCh. Got a 7R in it now apparently - and i'm told it's cracked badly so not a runner. Colin wanted to do a couple of frames the same as that one so asked if he could borrow it to copy. Payment was to be a new frame for them so it could be run again. Turned down flat I heard. Pity...

pete376403

7th January 2017, 18:57

husaberg

7th January 2017, 20:11

"It was Kuzmicki who... moved to the Rootes Group, and designed the extremely reliable and very fast Imp motor."
Really? I thought the Imp motor was a Coventry-Climax design for a lightweight fire pump. And "reliable"? My Imp used to eat head gaskets for lunch. Still a better car overall than the equivalent 850 mini though.

http://www.imps4ever.info/tech/fw_imp.html
http://www.imps4ever.info/tech/kuzmicki.html
Another detail from the original blog, it wasn't actually Joe Craig that discovered Leo

An intetesting story is that of Leo Kuzmicki. He was Polish, and escaped Poland to Britain and served in WW2 as a fighter pilot. He stayed on after the war but could only find employ as a cleaner at Bracebridge Street. Works mechanic, Charlie Edwards happened to be in conversation with Kuzmicki one day,and found out, that before the war, Leo was a lecturer on internal combustion engines at Warsaw University. Well, one thing led to another and Joe Craig put Leo to work on developing the 350 Manx, which up until then was as useful as a cast iron parachute.
Then Geoff Duke began winning on the Junior Manx. Geoff Duke was pretty impressed with Kuzmicki, who he reckoned expkained the theories of " squish " combustion chambers to him.
Joe Craig became jealous of Kuzmicki, which is why his work at Norton was never publicly acknowkedged.
Then Leo Kuzmicki went on to work on the Vanwall racing cars, but that is another story.........
The squish head Leo designed actually made the works 350 faster than the customer Manx 500.
Also missing from the above, is i believe it was Hele who convinced Craig to let Leo work on the bike.
Also the Vanwall was basically 4 works norton squish heads on a RR/Austin champ bottom end made in alloy.
Vanwall were part of the same ownership group (old boys directors network) as Norton so it was an inside project.
All the parts were valves etc were norton works parts obtained from Norton or via norton from their outside suppliers so not to arouse suspicion from potential competitors.

pete376403

7th January 2017, 21:26

ok -REdesigned. devil is in the details.

WilDun

8th January 2017, 08:33

Michael Moore

8th January 2017, 09:03

Here's the Piper 8v head

http://www.eurospares.com/graphics/piperhonda2.jpg

and here is the Lyster Honda

http://www.eurospares.com/graphics/Honda/LysterHonda.jpg

Michael Moore

8th January 2017, 09:32

You may like this article on the Zimmerman rotary valve 250

Grumph

8th January 2017, 11:58

Thanks for that pic of the Lyster Honda Michael. I thought I'd seen all the pics on your site but I'd never seen that one.
I also didn't know the bike had ever made it past testing...but that's obviously a meeting.
Shows up two things I'd already struck. The frame is long enough to fit damm near anything - probably is to the same dimensions as the Imp with it's separate gearbox. Note the big gap behind the motor...I think I can fit a small battery in there.
And although that version has low pipes, the frame downtubes are in the wrong place...It's even more difficult with a standard head casting.

As for the Piper Honda heads, you do wonder how many were made...Given the CB twins were flavour of the decade for UK Classic racing, you'd think at least one of those heads would have appeared - if only for sale.

WilDun

8th January 2017, 12:46

You may like this article on the Zimmerman rotary valve 250

Why was that Zimmerman machine not publicized more in the sixties?
Seems to me that it was at least 98% successful (as an engineering feat) but why did he not take advantage of it's success at competition? - maybe he was just happy to say that he had built a successful machine!
Of course the whole package, ie manufacture, presentation / marketing, sales and of course establishing a name etc. had to be considered to make it a success.
Seems to have been a great machine but in the wrong place and the wrong time - Americans then were just starting to take a real interest in bikes other than HD - (who incidentally were actually racing HD V twins at British meetings with Cal Rayborn etc on board) and the Japanese were also starting to make real inroads!
Pity that this one couldn't have shown it's paces!

Update : I now see that this machine was probably made in the late fifties, that's well before Japanese machines started to arrive in America, I don't believe many Americans would have been interested in small capacity machines at that time! :facepalm:

tjbw

8th January 2017, 12:51

You may like this article on the Zimmerman rotary valve 250

Yes, I liked it, thanks.

I thought it would be about the Daniel Zimmermann disc valve!

Didn't know about Merritt before, but wonder what became of his engine.

tjbw

8th January 2017, 13:06

Sorry if this has already been posted, but this Polish guy (Kuzmicki) who was a real development engineer (as opposed to the official ones) deserves to be honoured!
http://thevintagent.blogspot.co.nz/2010/02/leo-kusmicki-and-norton-squish.html

UPDATE :-This is the full article on Kuzmicki, (the guy Husa mentioned).
I saw a Manx Norton engine blueprint at the National Motorcycle Museum, near Birmingham. Don't recall any mention of Leo. He sure deserves recognition for his contribution.

husaberg

8th January 2017, 13:15

Of course the whole package, ie manufacture, presentation / marketing, sales and of course establishing a name etc. had to be considered to make it a success.
Seems to have been a great machine but in the wrong place and the wrong time - Americans then were just starting to take a real interest in bikes other than HD - (who incidentally were actually racing HD V twins at British meetings with Cal Rayborn etc on board)
:
The man in the forth pic is Lance Weil
One of the first americans to go over to blighty and compete on their own terms
https://www.kiwibiker.co.nz/forums/showthread.php/171300-Oddball-engines-and-prototypes?p=1131022229#post1131022229

327740 327742327741

http://www.eurospares.com/graphics/Laverda/Lance%20Weil%202.jpg

here is the squish head and detail of the Vanwall
327743327744
https://en.wikipedia.org/wiki/Vanwall
Funny enough squish heads was one of the reasons the Side valve KR harleys were so fast (for a side valve)

Michael Moore

8th January 2017, 14:19

husaberg

8th January 2017, 14:31

Rotating face gear camshaft operation
its pretty neat and oddball.
Charter lea which i knew about.
327746327747
Also it seams the ducati Capriolo 125 as well
327749327748

also
http://images.slideplayer.com/15/4674325/slides/slide_33.jpg

i was looking for the cone shaped cams that were used on i think Alfas but i can fine any.

Not what i was looking for but I found these though
https://i.kinja-img.com/gawker-media/image/upload/s--MBgnYDdU--/c_scale,f_auto,fl_progressive,q_80,w_800/kcfqmmwiye6dmfixdzyv.jpg

As for the Piper Honda heads, you do wonder how many were made...Given the CB twins were flavour of the decade for UK Classic racing, you'd think at least one of those heads would have appeared - if only for sale.

The piper heads would have missed the 72 period cut off.
I have one dated ad from a show somewhere it was at least 74-75

After diner he goes through a few MCM mags
Yip 1974.
327755

Grumph

8th January 2017, 16:21

Greg, I'd like to reorganize the website as it has gotten far larger than I ever imagined when I started it, and I'm a bit loathe to add more stuff if I'll just have to put it somewhere else later. I've got lots of things that have yet to find their way to the website. Someday . . . .

You and Rob - TZ350 - should compare notes on managing a runaway success, LOL.....

Thanks again for the pic, cleared up a couple of details anyway.

WilDun

8th January 2017, 23:41

I saw a Manx Norton engine blueprint at the National Motorcycle Museum, near Birmingham. Don't recall any mention of Leo. He sure deserves recognition for his contribution.

Yes I agree, Polish people did their best to rid Europe of Hitler (and did support Britain as best they could ) right through WW2, but never got a lot of recognition for their efforts and it seems they didn't get much after WW2 either!
I find it incredible that I had heard so much about Norton, Vanwall and also the Rootes group etc. yet had never heard of this guy!

husaberg

9th January 2017, 19:52

Greg, I'd like to reorganize the website as it has gotten far larger than I ever imagined when I started it, and I'm a bit loathe to add more stuff if I'll just have to put it somewhere else later. I've got lots of things that have yet to find their way to the website. Someday . . . .

Some stuff for your site Mike
327840
Dave Croxford with a Lyster 350 Manx

327836327837327838327839
The remaining Lyster CB450/500

Plus a few more pics i harvested.
https://www.kiwibiker.co.nz/forums/album.php?albumid=5076

Grumph

10th January 2017, 05:50

Some stuff for your site Mike
The remaining Lyster CB450/500

In point of fact as i think I've said on the chassis thread, even Colin didn't know how many of the CB450 frames had been made.
They were made for him by Grand Prix Metalcraft in London - who also made Peter Williams Arter Matchless frames - and if he was asked for a frame he simply referred the enquirer to GP Metalcraft and forgot about it....

husaberg

10th January 2017, 07:37

In point of fact as i think I've said on the chassis thread, even Colin didn't know how many of the CB450 frames had been made.
They were made for him by Grand Prix Metalcraft in London - who also made Peter Williams Arter Matchless frames - and if he was asked for a frame he simply referred the enquirer to GP Metalcraft and forgot about it....

Reading that story i got the impression the Jack Williams peter father might have been related to Mrs Lyster.

Grumph

10th January 2017, 14:44

Reading that story i got the impression the Jack Williams peter father might have been related to Mrs Lyster.

Read the last page again....

husaberg

10th January 2017, 17:05

Read the last page again....

The last page is quite different fron the earlier one. second page middle of second colum

Grumph

10th January 2017, 18:28

The last page is quite different fron the earlier one. second page middle of second colum

Yes, I saw that...that writer is notorious for getting his tenses wrong IMO. He meant - the head was done by the uncle of the owner's wife...
Just as well we're not reading it in french as the possibilities for error are magnified.....

husaberg

10th January 2017, 18:40

Yes, I saw that...that writer is notorious for getting his tenses wrong IMO. He meant - the head was done by the uncle of the owner's wife...
Just as well we're not reading it in french as the possibilities for error are magnified.....

French, do you think i should i write him a letter.;)

ken seeber

10th January 2017, 23:17

Having had to do a demo for an unbeliever, I thought that engines can take various forms, so figured that this one might also be eligible. Not unusual, everyone has got one? :ar15:
Model: Passion Bird
Bore: 65
Stroke: 750
Swept capacity: 2.488 litres
Connecting rod length: zero
Compression ratio: zero
Lubrication: zero
Piston weight: approx. 180 to 200 gms
Piston material: organic or more simply, a potato
Ignition: piezo
Fuel: mosquito repellent, hair spray, petrol, etc
Output: potato piston projected around 150 metres with a decent bang, lots of giggles & can scare the shits out of the unwary
Basic construction material: PVC pressure pipe and fittings.

https://youtu.be/JtYcti0Y6WI

WilDun

11th January 2017, 22:18

Having had to do a demo for an unbeliever, I thought that engines can take various forms, so figured that this one might also be eligible. Not unusual, everyone has got one?

Well Ken - what can I say? Everything you said is more or less correct! .............. hope you're not trying to divert our attention from the slider engine project!! :msn-wink:

WilDun

11th January 2017, 22:22

French, do you think i should i write him a letter.;)

My head was done (in) by the wife ........ porquoi? ....... je ne sais pas - it was fine before that!! :laugh:

lohring

13th January 2017, 00:33

WilDun

13th January 2017, 11:43

I think this (http://www.pattakon.com/pattakonPatWankel.htm) seriously qualifies as an oddball engine. It may succeed in sealing the rotor better than all the other rotary engines. The plug in the inner element, rotor surface finish and accuracy, as well as other factors may give problems. I want to see a prototype. Lohring Miller

Yes, this guy (and his colleagues I guess) certainly have a lot of very interesting refreshing ideas (and fantastic animations as well) ) but let's face it, all ideas spring from someone else's unfulfilled or abandoned ideas and as you say it would be nice to see a prototype.

A while ago he appeared on the ESE thread, which as you know is mostly about members who want to display their efforts to improve existing two stroke technology in Bucket racing etc. - In fact that's basically why this thread was started, ie in order to prevent the ESE thread becoming too cluttered with other stuff!

Moving to this thread would have made a lot of people take a keen interest in what he was trying to get across....... but unfortunately he didn't - even though we suggested he should. :facepalm:

WilDun

19th January 2017, 12:44

Sorry Ken, I just nicked this post from ESE, but ESE had moved on (as it does!) and I didn't want to go back and bring it up again - that's where this thread comes in.

Below is an excerpt from:

http://www.motorsportmagazine.com/opinion/motogp/after-117-years-triumph-s-first-gp-win

"Honda’s CBR600 has powered Moto2 since its inaugural 2010 season, but the 600 is nearing the end of its shelf life, so the class needs a new engine. Many alternatives were considered, including a return to 250 two-strokes, with a 250cc v-twin version of the Suter 500 V4.

Triumph's new 765cc triple that will power Moto2 from 2019
A 750 (in fact 765cc) makes a lot of sense because Moto2’s job is to get riders ready for 260 horsepower MotoGP bikes, so they need to learn to spin the rear tyre and use the throttle to steer. This season Moto2 gets traction control and other rider aids for the first time, because riders also need to learn about electronics before they graduate to the premier class. Traction control isn’t really required by a 125bhp 600 but it will come in handy with a 160 horsepower 765."

So close yet so far.

Better get it ready for next time Fletto. :psst:

Probably that engine was inspired by the very successful Smith's Triumph as used in BSB and in road races such as the TT etc.

Very interesting link - I had a lot of respect for Doug Hele, Val Page, Vincent etc. in fact all the brilliant engineers who didn't really get a fair go from management.
When I look back at pics of the Tiger 100 etc I now realize what good looking, uncomplicated machines they were!
The only Triumph I ever owned was a Tigress scooter (which BTW was a good machine), it handled just as well as their bikes! - it had a 250cc twin four stroke engine which was originally used in the ill fated Sunbeam S2 motorcycle built for the American market.

I rode a Norton Dominator 600 and was very fond of that, but I believe that Triumphs had the edge on speed - however the Norton handled better! (and yes Frits, it did leak oil!) :yes:

I was also very interested in Doug Hele's design for a balance shaft for the vertical twins and rejected by management as you'd expect! - I believe Ducati used a similar arrangement in their single cylinder 500 just a few years ago.
I think all this may have been discussed a while back in this thread.

It was sad to see Doug Hele ending up at British Seagull to see his working life out, but at least they could still offer him a job which is more than the British motorcycle industry could after they collapsed under the weight if the Japanese!

Michael Moore

19th January 2017, 14:09

Frederick Lanchester patented balance shafts for engines in the early 20th century:

https://www.google.com/patents/US1163832

Nothing (or very little) new under the sun!

cheers,
Michael

WilDun

19th January 2017, 18:27

Dr Lanchester also invented the pre-selector gearbox, seems he was a clever man but would not suffer fools!

Triumph twin balancer (by Doug Hele).

328050

Grumph

19th January 2017, 19:08

Dr Lanchester also invented the pre-selector gearbox, seems he was a clever man but would not suffer fools!
Triumph twin balancer (by Doug Hele).

That's a Laverda 180 deg triple crank with a captive center rod....I remember reading an interview with Hele where he said they'd stripped a CB500 Honda four. They realised they didn't have the machinery to make it - or the capital to buy the machinery...I suspect Triumph/BSA couldn't have made that crank setup.

Lanchester I believe said that the driver's sight line in a car should be at the same level as a man walking. Wonder how he'd have liked the low driving positions of today.

husaberg

19th January 2017, 19:22

Dr Lanchester also invented the pre-selector gearbox, seems he was a clever man but would not suffer fools!

Triumph twin balancer (by Doug Hele).

328050

Alfred Scott from memory invented the kickstart.
Here is some other intersting stuff
http://www.scotttechnicalities.com.au/technicalities/Chapter%202/2.1%20Engine%20Topics.pdf

Michael Moore

20th January 2017, 04:17

They realised they didn't have the machinery to make it

I've got a small book put out by Pratt and Whitney about the company history. One of the anecdotes I remember was when they were gearing up for WW2 production. They had a group of industry leaders/boffins over from England to tour an engine plant to discuss production on both sides of the Atlantic. The visitors were looking over a table of parts and commenting how they would struggle to make them to that standard, if they could at all. When they were told that was a table of parts that had failed QC inspection they thought they were having them on.

cheers,
Michael

WilDun

20th January 2017, 07:57

I've got a small book put out by Pratt and Whitney about the company history. ................. When they were told that was a table of parts that had failed QC inspection they thought they were having them on.

cheers,
Michael

Small countries ( or any third world country as well, big or small) pull through (or lose) using anything they have to the fullest extent, an extreme example would be Vietnam, where the people could use any materials which we would have discarded to make just about anything!

Large industrial countries win through because of their big populations and resources and work hard producing excess goods, they pick out the best for themselves and dump as much as possible in the poorer countries.

Anyway, the point is that Britain, although it had been rich through it's empire, was now cut off from that, so at that time was desperate and had very little in the way of hardware or resources to take on Germany but were still coming up with some amazing technology using only the old machinery and techniques they had to produce it. (eg they finished the bearing journals on the Merlin aircraft engines by hand lapping them!), whereas later when Packard in the US also started to produce them for the Mustangs and Mosquitoes used the latest technology to finish grind them........ Bet they (the British) would have used that table of QC failed parts anyway!

New Zealand has always been a small country (pretty much the same size as Japan) but with a much smaller population and so was not always able to get hold of all the latest technology, however still came up with some brilliant ideas and people, who made an impact on the world.
Some last remains of that "make do with what you have" spirit, can still be seen in the Bucket Racing fraternity! :yes:

Money is not only the root of all evil, it is the root of everything ......... an unfortunate state of affairs! :(

Michael Moore

20th January 2017, 08:36

WilDun

20th January 2017, 10:59

I don't think it was a case that the industry folks from the UK couldn't make the parts to the tolerances needed because they clearly could make some excellent stuff, but it was more that they couldn't do it on a production basis with the quantities that were expected.

Too, it wasn't like here in the States we were having factories bombed on a near daily basis the way they were in England. We were busy putting up brand new factories with brand new tools in them, not looking to see which crater the tool had ended up in after the raid.

cheers,
Michael

Had a look through my last post, - did I say all that stuff? - think I talk too much - but that's me, for better or for worse! :o

Yes Michael all true but as I said money is the root of everything and to be honest, you guys did save their bacon with that!
The unfortunate thing was they had to hand over most of their technology (in lieu of cash) to repay the debt! - But then it was either that or be on the receiving end of a tyrant!

How is your foundry work progressing these days? you were doing well a while back! not that this thread needs to catch any overflow from the foundry thread of course, unlike like ESE sometimes does.

Michael Moore

20th January 2017, 11:08

It has been quiet on the foundry front but I did some CNC stuff for Jeff and he's going to do the mold boxes and match boards for my cylinder head pattern. I don't like woodwork! A couple of heads before the new race season starts would be of help to several people.

husaberg

20th January 2017, 16:51

I've got a small book put out by Pratt and Whitney about the company history. One of the anecdotes I remember was when they were gearing up for WW2 production. They had a group of industry leaders/boffins over from England to tour an engine plant to discuss production on both sides of the Atlantic. The visitors were looking over a table of parts and commenting how they would struggle to make them to that standard, if they could at all. When they were told that was a table of parts that had failed QC inspection they thought they were having them on.

cheers,
Michael

The Brits used to get around the tolerences by using selective fit.
From what i understand Harley Davidson are actually still made like that, as they can't achive Japanese style Production tolerences.

pete376403

20th January 2017, 21:25

When an engine may only last a few hours before the plane is shot down, is it worth the effort to make parts to such fine tolerances?

WilDun

20th January 2017, 23:11

When an engine may only last a few hours before the plane is shot down, is it worth the effort to make parts to such fine tolerances?

That's like saying don't worry about the engine because a bucket race only lasts about quarter of an hour!
Those guy's lives were at stake and the engines needed to be performing as near perfectly as possible - they didn't all get shot down and as far as they were concerned they weren't going to be!!

husaberg

20th January 2017, 23:21

That's like saying don't worry about the engine because a bucket race only lasts about quarter of an hour!
Those guy's lives were at stake and the engines needed to be performing as near perfectly as possible - they didn't all get shot down and as far as they were concerned they weren't going to be!!

I am a bit more callous as it took much longer and was much more expensive to train a pilot than build a decent engine.
Zee Germans took this philosophy too far though. As it didn't matter if their tanks were twice as good as the Russians or the Americans, if the Russians or the Americans built 20X as many tanks.

Frits Overmars

20th January 2017, 23:56

When an engine may only last a few hours before the plane is shot down, is it worth the effort to make parts to such fine tolerances?Yes it was, Pete. It's a bit like the two men who planned a foot safari through lion country, and one of them started looking for the best running shoes.
His mate sneered: "Do you think you can outrun a lion with those?" The answer was: "I don't need to; I only need to outrun you!"

But yes, the Germans tended to overdo it with their war tolerances. They can't help themselves; it's in their nature. And I can tell you that it makes a lot of difference,
whether you do R&D in Germany or in Italy! There's a saying that in heaven you deal with German engineers and Italian Chefs, and in hell it's the other way around :msn-wink:.

Michael Moore

21st January 2017, 05:02

I think Kevin Cameron mentioned in passing in one of his columns that the Allies made so many of the big radial P&W engines that they probably could have just dropped them instead of making bombs, and in any event it wasn't uncommon for those that returned to have blank spots on the engines where cylinders had blown off in flight to rain down on the countryside below.

I recently watched a series on warbird restoration that was shot in England and several times they remarked how North American and the other US manufacturers were known for keeping tolerances close enough that it was possible to unbolt a wing or other major part from one plane and bolt it up on another one without any fussing with the fit. I gathered that may not have been quite the case with the English planes.

cheers,
Michael

Grumph

21st January 2017, 07:05

I have an old friend who is now the chief engineer at the Alpine Fighter Collection here in NZ. Don't see him now as he's basically given up bikes. However talking to him about some of the problems encountered doing the restorations was an eye opener. Marks of Spitfire ? They're ALL different....The Russian fighters - of which they have a number - hand built. American ? Just like repairing a car, pull off a wing, bolt another on, no problems.

Talking WW2, my father had a story...In charge of transport on Crete, when it became apparent that surrender was imminent, gave the order to destroy the trucks and supervised it too. Drained oil and water, drove them to spots that would block any landing zones and revved shit out of them till they seized solid.

About a week later, after capture and his wounds sorted enough to move him, he was driven to the ship to go to POW camp - in one of his destroyed Bedfords. Apparently it smoked badly and made some ominous noises - but ran.
They'd been run on a form of synthetic oil supplied from the UK - and they'd been told the trucks wouldn't need any oil changes for as long as they had them.
He was impressed. Post war in London sitting the last section of his AMIMechE, he asked about the oil. Couldn't be told, still secret.

WilDun

21st January 2017, 10:05

....... so I gathered that may not have been quite the case with the English planes.
cheers,
Michael

Michael - British planes! - In the modern UK, the English are English (and considered British), but being British does not not necessarily mean you are English!
Then, just about everyone else makes that mistake as well (including the Germans) so what the hell! :laugh:

Marks of Spitfire ? They're ALL different....The Russian fighters - of which they have a number - hand built. American ? Just like repairing a car, pull off a wing, bolt another on, no problems.

...............They'd been run on a form of synthetic oil supplied from the UK - and they'd been told the trucks wouldn't need any oil changes for as long as they had them.
He was impressed. Post war in London sitting the last section of his AMIMechE, he asked about the oil. Couldn't be told, still secret.

Yes the Americans got it sussed ok and probably all thanks to Henry Ford and others too!

Don't think that lubricant would be on the secret list now, bet some of the big oil companies have got it by now.

Pursang

1st February 2017, 23:43

Here is a link to a pretty cool book on aircraft engines, printed back in 1917. (Only 100 yrs. ago)

http://www.ajhw.co.uk/books/book61/book61.html

It is amazing how much engine technology had already been pretty highly developed in the years since the Wright bros. flight in 1903.
(The 2 strokes needed some more work, but. )

A lot of the development didn't get into American car engines 'til nearly the end of the century.

Some sections have been censored, due to the US entry to WW1.

If you like Historical oddball engines it's worth a look.

Cheers, Daryl.

lohring

2nd February 2017, 02:25

The pre war two strokes were interesting as well. Below is a NACA tech report on some of the possibilities the Germans were considering.

lohring Miller

328277

WilDun

6th February 2017, 09:45

Just to kickstart this sluggish thread again!

Note: Even though I didn't reply to, or acknowledge them, I did find the last two posts very interesting.

These video clips are probably quite old but I admire this Aussie guy's enthusiasm - his design obviously works very well and I'm sure KEN in particular would be interested!
I am interested because it no doubt feels like a bike - If I rode a two wheeler and fell off, it would be curtains for me, such is my fragile physical state. so I would like to try something like this, I think that would definitely be the machine for me!

https://www.youtube.com/watch?v=-KBJOYkMob0
https://www.youtube.com/watch?v=dY3HthkejoI

tjbw

6th February 2017, 09:59

husaberg

6th February 2017, 09:59

https://translate.google.com/translate?sl=auto&tl=en&js=y&prev=_t&hl=en&ie=UTF-8&u=http%3A%2F%2Fwww.supermototecnica.com%2F2015%2F1 0%2F16%2F5423%2F&edit-text=&act=url

I have posted a video of this engine before.

WilDun

6th February 2017, 14:52

husaberg

6th February 2017, 15:19

Some very interesting stuff ( ie in the last few posts) -
I don't think the Honda balancing act would save me if I threw a leg over a two wheeler though - I could still fall off!

Also a very interesting Yamaha V4. The guy doesn't even claim to be an engineer but I would say that he is now! - I wonder if someone has translated it into better English yet? it's reasonably easy to get the gist of what he's saying though.

here is the video it also covers someone elses Honda CB250R 4's turned 5's plus 3'sand a homemade MV
EDit Actually the Yamaha v4 is a different engine from a different more froggy person as well.

https://www.youtube.com/watch?v=_ZZApGl8H2M

http://motoreduetempi.blogspot.co.nz/2012_04_01_archive.html

WilDun

7th February 2017, 08:23

here is the video it also covers someone elses Honda CB250R 4's turned 5's plus 3'sand a homemade MV
EDit Actually the Yamaha v4 is a different engine from a different more froggy person as well.

https://www.youtube.com/watch?v=_ZZApGl8H2M

http://motoreduetempi.blogspot.co.nz/2012_04_01_archive.html

Weird things happening here again - I'm just getting blank pictures (might be just videos of course) but it's annoying me!
Probably is only on my computer but just on this site.
Maybe I pressed a wrong button again somewhere! - can anybody give me a clue?, - I'm clueless! :rolleyes:-

Your last video clip, (the one above) just shows up as a black screen! and it's the last of a lot of "no show" videos.

tjbw

7th February 2017, 09:08

Weird things happening here again - I'm just getting blank pictures (might be just videos of course) but it's annoying me!
Probably is only on my computer but just on this site.
Maybe I pressed a wrong button again somewhere! - can anybody give me a clue?, - I'm clueless! :rolleyes:-

Your last video clip, (the one above) just shows up as a black screen! and it's the last of a lot of "no show" videos.

It was working earlier, however seems to have a problem with youtube now!

Update - working again!

WilDun

7th February 2017, 15:18

Just checked it out, all the videos which are posted directly into this forum have disappeared and all I can see is a blank, black picture where they should be. - so Husa's posts with videos I never get to see (most frequent)! ................ anybody able to help? - There must be a simple answer!

husaberg

7th February 2017, 15:50

Weird things happening here again - I'm just getting blank pictures (might be just videos of course) but it's annoying me!
Probably is only on my computer but just on this site.
Maybe I pressed a wrong button again somewhere! - can anybody give me a clue?, - I'm clueless! :rolleyes:-

Your last video clip, (the one above) just shows up as a black screen! and it's the last of a lot of "no show" videos.

Its likely your browser what are you using Edge? i assume you are on Windows 10?

WilDun

7th February 2017, 16:01

Its likely your browser what are you using Edge? i assume you are on Windows 10?

Yes, Windows 10 but somewhere along the line (approx. one and a half weeks ago}, something changed - and I don't know what the hell "edge" is! I guess its the browser which comes with Windows 10, but I never use that. - but i'm pretty sure I've disturbed some setting or other.

husaberg

7th February 2017, 16:30

Yes, Windows 10 but somewhere along the line (approx. one and a half weeks ago}, something changed - and I don't know what the hell "edge" is! I guess its the browser which comes with Windows 10, but I never use that. - but i'm pretty sure I've disturbed some setting or other.

Just try reloading another browser, likely an update fixed it for you.
My old one never use to show the PNG pics that frits always posted until i saved them.
What logo does you broswer show an e?

WilDun

14th February 2017, 09:24

Ok thanks, all good now!

Problem actually was my WiFi adapter which was on the way out, (it finally bit the dust!).

tjbw

27th February 2017, 07:19

WilDun

28th February 2017, 11:19

What you need Will, is some protection over your head, like this little Rudezon. It's a modified Volvo car, with a V8 Evinrude boat engine ;)

More info here: http://www.engineswapdepot.com/?p=5141

https://www.youtube.com/watch?v=mrhsUXnodfw

No,No, God forbid! - if I could manage to get into that contraption I'd never be able to climb out of it! - I ran out of space in my garage to keep my little Honda Gyro tilting trike (and my main lathe also) but I do like tilting vehicles, motorcycle feel, but with less risk of falling off!

I have always loved two strokes (especially in bikes), but there are still one or two things about them which irritate me a lot - One is the amount of embarrassing smoke they continue to emit, two is the embarrassing size of their exhaust chambers, especially in larger cylinder sizes and in multi cylinder engines, and also fuel consumption - all this no doubt can be overcome (at a cost) and would leave four strokes for dead in just about every respect, but in order to achieve that everything would have to become complicated, - a far cry from the "simple" two stroke of the past. Trouble these days is, with motorcycles, people will accept expense and complication, ie if it's fashionable and will gain them a couple of horses, even if they can't use them - except for bragging rights!
I think the two stroke could survive in snowmobiles, karts and aircraft and ( thanks to the work already being done) are surviving, also the scales could just be starting to waver towards the two stroke in motocross!

WilDun

1st March 2017, 12:20

Pity about the grotesque big chambers needed for two strokes! - needing monstrous things like this keeps them from production surely (for the road, not racing) - isn't there a better and neater option - like forced induction and lower exhaust ports? - ok I'll probably get my theory blown out of the water, but worth a try! :rolleyes:
https://www.youtube.com/watch?v=kjJ1iYtg_OM

Then there's this engine which I first saw a few years back - it looked very promising then but no one seems to want to take it on! (tried and being tested by Ilmor, a well known company)
I wonder if this principle could be used in a two stroke to use up all that unburnt stuff which comes out of the exhaust? I guess the big disaster of the Wankel makes companies improve what they've got rather than make radical moves!
https://www.youtube.com/watch?v=u0uPmrSRM7w

Michael Moore

3rd March 2017, 07:35

Pity about the grotesque big chambers needed for two strokes! - needing monstrous things like this keeps them from production surely (for the road, not racing)

But aren't the large ones meant for maximum RR power? I've got a Pro Circuit II pipe for a 250 KTM SX sitting here next to me, and the major diameter is just over 4", and this pipe is supposed to extend the power band (not necessarily increase the power) for another 1-1.5K RPM. So if you had a 500 2T twin making 100 hp would the exhausts be that much bigger than on an 4T? If you are looking for a milder engine with 60-70hp the exhausts would probably be smaller in diameter.

One advantage to the 2T engine is there's not a large sump hanging off the bottom of the engine getting in the way of tucking the exhaust in better.

Having to fit a couple of exhausts the size of the one on this Zabel RGV might be a big task.

Allegedly Walter Kaaden remarked that you know when the 2T exhaust is getting to be the right shape when you can't put it on the bike without it dragging on the ground, burning the rider, or requiring the relocation of some other major component (which might include the rider).

cheers,
Michael

ken seeber

3rd March 2017, 12:48

The 5 stroke would fall under the category of a "bottoming cycle" principle where any waste energy is utilised. I would suppose the expansion chamber as we know it also falls into this category as it provides energy to over charge the cylinder.

This drum charger is perhaps an alternative.

http://newatlas.com/drum-charger-cheap-motorcycle-turbo/46648/

Maybe it is less obtrusive than an expansion chamber.

Back to the 5 stroke, possibly an adaption of this could be applied to a 2 stroke ?

WilDun

3rd March 2017, 13:51

So if you had a 500 2T twin making 100 hp would the exhausts be that much bigger than on an 4T? If you are looking for a milder engine with 60-70hp the exhausts would probably be smaller in diameter.

That is probably quite true but I guess I was referring to large 700cc+ engines (as most road machinery is today). I think a large part of the problem is where the "fat part" is located in the pipe.
Sadly, the four stroke is now solidly ingrained in the minds of the younger generation most of whom did not grow up with the two stroke and who may not even have heard of a two stroke, except in chainsaws etc and now no longer fashionable - all very unfortunate!

One advantage to the 2T engine is there's not a large sump hanging off the bottom of the engine getting in the way of tucking the exhaust in better.

Maybe someone should have listened and realized the old designers (inspired no doubt by aircraft engines) were right after all, when they used dry sumps and oil tanks!

Allegedly Walter Kaaden remarked that you know when the 2T exhaust is getting to be the right shape when you can't put it on the bike without it dragging on the ground, burning the rider, or requiring the relocation of some other major component (which might include the rider).

There you go, - all those years ago he predicted what I was going to say! :laugh:

WilDun

3rd March 2017, 14:15

husaberg

3rd March 2017, 17:40

But aren't the large ones meant for maximum RR power? I've got a Pro Circuit II pipe for a 250 KTM SX sitting here next to me, and the major diameter is just over 4", and this pipe is supposed to extend the power band (not necessarily increase the power) for another 1-1.5K RPM. So if you had a 500 2T twin making 100 hp would the exhausts be that much bigger than on an 4T? If you are looking for a milder engine with 60-70hp the exhausts would probably be smaller in diameter.

I saw Lozza (2tinstitute) post a rule of thumb for air cooled RD350's on the net somewhere, the belly had to be kept ultra-small by modern std to avoid over scavenging the already too small crankcases.likely applies to tz350's as well.

pete376403

3rd March 2017, 23:36

Looks quite simple and easier to tuck away because of the shape (even if it is big), maybe we could even locate it in the fairing!

If Ilmor took the 5 stroke concept seriously then it must have some merit!
Another supercharger/turbocharger that seemed to have merit, then disappeared was the Brown Boveri Pressure wave. Belt driven but used exhaust gas to directly compress intake air. Ferrari used it for a while in FI.

Frits Overmars

4th March 2017, 00:07

Another supercharger/turbocharger that seemed to have merit, then disappeared was the Brown Boveri Pressure wave. Belt driven but used exhaust gas to directly compress intake air. Ferrari used it for a while in FI.This Brown Boveri supercharger became known as the Comprex. Mazda used to play with it too, in their 626 Capella.
I'm not sure whether we should call the Comprex a turbocharger because its rotary motion is not driven by an exhaust gas turbine, but it does use exhaust gas energy to compress the intake air. Development is still going on; today's version is called the Hyprex.
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Frits Overmars

4th March 2017, 00:42

If you want to supercharge an engine, you must blow through the port that closest last. In a four-stroke engine that's no problem, but supercharging a two-stroke tends to be less effective. You blow through the transfer ports, but when these close, the exhaust port is still open, so you cannot really create a high pressure in the cylinder.

Closing the exhaust port before the transfer ports was done in the pre-war blown DKW racers with their split-single layout and in the Jumo 205 uniflow engines
with a crankshaft at either end of the cylinders. But as supercharging was forbidden after the war, nobody seems to have given it much thought since then. Well, I did.

A two-stroke exhaust pipe is a supercharger, albeit without any moving parts, so it is not affected by the supercharger ban. And a good pipe can triple the power of a competition two-stroke, so you would think that it is quite effective. But it doesn't stand a chance against the power of a blown four-stroke.

Let's take a look at the engine I am most familiar with, the Aprilia RSA. At exhaust opening the pressure of the spent gases in the cylinder is about 12 bar abs.
At exhaust closure the pressure of the fresh mixture in the cylinder is about 2 bar abs. If we could raise that to say 4 bar, we would about double the power.
There is plenty energy in the spent gases, if only the exhaust pipe could deal with it more effectively.

Pondering about this, I ran into a forty-year old patent wherein the full pressure of one cylinder's exhaust pulse is used to charge the neighbour cylinder of a 180° parallel twin. It requires an exhaust timing of well over 180° but hey, if it works... And we could get away with a single exhaust pipe of modest dimensions. Think about it.

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WilDun

4th March 2017, 11:19

If you want to supercharge an engine, you must blow through the port that closes last.........supercharging a two-stroke tends to be less effective. You blow through the transfer ports, but when these close, the exhaust port is still open, so you cannot really create a high pressure in the cylinder.

Closing the exhaust port before the transfer ports was done in the pre-war blown DKW racers with their split-single layout .............,but as supercharging was forbidden after the war, nobody seems to have given it much thought since .........

A two-stroke exhaust pipe is a supercharger, albeit without any moving parts, so it is not effected by the supercharger ban. And a good pipe can triple the power of a competition two-stroke, so you would think that it is quite effective. But it doesn't stand a chance against the power of a blown four-stroke.

................. At exhaust opening the pressure of the spent gases in the cylinder is about 12 bar abs. At exhaust closure the pressure of the fresh mixture in the cylinder is about 2 bar abs. If we could raise that to say 4 bar, we would about double the power.

I ran into a forty-year old patent wherein the full pressure of one cylinder's exhaust pulse is used to charge the neighbour cylinder of a 180° parallel twin. It requires an exhaust timing of well over 180° but hey, if it works we could get away with a single exhaust pipe of modest dimensions.

Now we're talking Frits!

I hadn't realized that DKW had exhausts which closed before the transfers, but I did wonder if that was feasible .... now I know it was.

So maybe the idea of using the "semi spent" exhaust gases for productive power, also by using direct forced induction to the "transfers" etc. we can get rid of bulky exhaust chambers, crankcase pumping and petroil lubrication - all in one go!
In fact a complete re-design of the two stroke! (last chance?).

This thread may be a good place to discuss all the possibilities (outside the rulebooks) of new experimental stuff, or ideas from the past abandoned for various reasons ........ all without treading on people's toes in other threads! but I'm sure there will always be an unavoidable overlap.

tjbw

5th March 2017, 09:42

No,No, God forbid! - if I could manage to get into that contraption I'd never be able to climb out of it! - I ran out of space in my garage to keep my little Honda Gyro tilting trike (and my main lathe also) but I do like tilting vehicles, motorcycle feel, but with less risk of falling off!

I have always loved two strokes (especially in bikes), but there are still one or two things about them which irritate me a lot - One is the amount of embarrassing smoke they continue to emit, two is the embarrassing size of their exhaust chambers, especially in larger cylinder sizes and in multi cylinder engines, and also fuel consumption - all this no doubt can be overcome (at a cost) and would leave four strokes for dead in just about every respect, but in order to achieve that everything would have to become complicated, - a far cry from the "simple" two stroke of the past. Trouble these days is, with motorcycles, people will accept expense and complication, ie if it's fashionable and will gain them a couple of horses, even if they can't use them - except for bragging rights!
I think the two stroke could survive in snowmobiles, karts and aircraft and ( thanks to the work already being done) are surviving, also the scales could just be starting to waver towards the two stroke in motocross!

So the criteria include:

No bevel gears
No big fat exhaust pipes
Easy to get into
Must have tilting motorcycle feel
...

https://www.youtube.com/watch?v=sVex_mDcMgk

WilDun

5th March 2017, 10:53

So the criteria include:

No bevel gears
No big fat exhaust pipes
Easy to get into
Must have tilting motorcycle feel
...

https://www.youtube.com/watch?v=sVex_mDcMgk

Well, I didn't mention bevel gears - anyway that contraption really takes the cake! and to be honest, the only "safe" braking method is exactly what the guy riding it used!
Another (albeit negative) thought is :- Imagine what would happen if a piece of gravel got caught on that bloody great bearing at 50mph!!! :shit:

Oh and I see why they used a lady on that machine on the old photo - a guy getting things caught on that sprocket just doesn't bear thinking about !

Frits Overmars

6th March 2017, 01:31

the only "safe" braking method is exactly what the guy riding it used!Well, he used the gate he ran into at 2:32. But what if there's no gate at hand?

tjbw

6th March 2017, 14:03

...

Another (albeit negative) thought is :- Imagine what would happen if a piece of gravel got caught on that bloody great bearing at 50mph!!!
...

That was my first thought as well. It would give a new meaning to "going for a spin" ;)

Also, vision is obscured by the wheel, imagine what would happen if two monowheels are on a collision course!

WilDun

6th March 2017, 20:37

That was my first thought as well. It would give a new meaning to "going for a spin" ;)

Also, vision is obscured by the wheel, imagine what would happen if two monowheels are on a collision course!

I guess anything can be achieved if you chuck enough money at it - a camera on each side of the wheel and a monitor of course.!

How about using the "wheel rim" as giant rotor of a stepper motor, that stepper motor being controlled by a computer and using traction control type hardware as sensors, that way braking and acceleration will be be taken care of.
In theory a heavier pilot would be able to brake more heavily than a light one! but if there was a computer glitch and the "pilot" went for a "spin", think about the unbalanced forces!!
Could even be driverless! - hang on - then there would be thousands of the bloody things careering around the streets with no one aboard and nowhere in particular to go - what would be the point in that? - how about Pizza delivery?

I'm beginning to think that in reality bucket racers is as far as technology needs to go and anything further than that is a step too far - even that can sometimes get out of hand!
:msn-wink:

tjbw

7th March 2017, 04:49

I guess anything can be achieved if you chuck enough money at it - a camera on each side of the wheel and a monitor of course.!

How about using the "wheel rim" as giant rotor of a stepper motor, that stepper motor being controlled by a computer and using traction control type hardware as sensors, that way braking and acceleration will be be taken care of.
In theory a heavier pilot would be able to brake more heavily than a light one! but if there was a computer glitch and the "pilot" went for a "spin", think about the unbalanced forces!!
Could even be driverless! - hang on - then there would be thousands of the bloody things careering around the streets with no one aboard and nowhere in particular to go - what would be the point in that? - how about Pizza delivery?

I'm beginning to think that in reality bucket racers is as far as technology needs to go and anything further than that is a step too far - even that can sometimes get out of hand!
:msn-wink:

Yes, I was thinking of two cameras as well, didn't think about the stepper motor though, I like that idea. I was thinking there might be something in Segway technology that could be exploited.

You made me laugh re the pizza delivery, but what I think you should do is form a company, called Deliverwi, and do local deliveries using ncopters ;)

WilDun

7th March 2017, 09:34

Yes, I was thinking of two cameras as well, didn't think about the stepper motor though, I like that idea. I was thinking there might be something in Segway technology that could be exploited.

You made me laugh re the pizza delivery, but what I think you should do is form a company, called Deliverwi, and do local deliveries using ncopters ;)

Well ok, I'll do that but think I should call it "I Will Deliver" or maybe more appropriately " Will I Deliver" :laugh:

"Segway" was the name I was trying to remember, - One thing to bear in mind is that Segway was killed by falling off one of his "safe" contraptions!!

FRITS,
The cost of gates and fences is prohibitive and if they were everywhere - then just think of the message that we would be sending to our aspiring but more timid monowheel riders! :laugh:

Anyway no matter which way you look at that design, it is compromised by being completely dependent on electronic control and the only brake anchor available is dependent on the weight of the engine and the "rider/driver/pilot?" giving it severely limited stopping power (as in all monowheels). - to be serious you should have a brake anchor bearing somewhere on the ground, as far out as possible, ie if you want to sit inside the wheel.

WilDun

17th March 2017, 12:25

Talking of Oddball Engines, I see that the "everlasting" Ryger debate has erupted again over at ESE, with a lot of vicious stuff being spat out as well! - why is that? he may have been a little too premature with claims but hasn't really hurt anyone ( his own credibility has taken a knock though) but it's heartening to see that a certain well known and respected two stroke tuner from NZ has decided to retract some comments and give him a break! also a guy from Sweden gave some measured support.
Maybe Luc should just plod on, stop wasting time arguing and it might all eventually work out!

Regarding giving out ALL your info on the forum there are certain "gentlemen" in this world who will look at every idea seriously (credible or not), spend their days sifting through all this stuff, - next thing you know "whammo" a huge company suddenly comes up with a "brilliant" idea which they had "thought up" and proceed to sell it for a very competitive price! (no built in safety factor though, just a bare minimum of everything)!

I remember a couple of American guys managed to successfully come up with and sell lightweight electronic spark ignitions for the bigger model aircraft (petrol) engines and were trundling along fine, then a company from that big country we all know well, decided they were ripe for the picking and mass produced something almost identical and at a cheaper price than these small companies could manage - that's just how it is I guess! :rolleyes:

tjbw

17th March 2017, 12:59

WilDun

24th March 2017, 10:20

Luc's a great 2 stroke enthusiast, just like the rest of us. I think he could contribute a lot here, if he wasn't so busy with Ryger.

Seems to me that in recent years the resurrection of the two stroke engine is not progressing as intended - and many (good) ideas just seem to evaporate and disappear (except in Buckets of course). The Bimota V Due, The Suter, the Ryger and others being the latest, but at least the outboard motors, snowmobiles and Karts are managing to keep a glimmer of hope going!

We have many little success stories with fuel injection (eg. Flettner's Kawasaki enduro efforts) but none of the big companies will take any notice, let alone pour money into something which for the future is probably more promising than the ever growing sophistication (read complication and cost) of the four stroke and all caused by legislators who only read the impressive graphs presented by certain domineering companies who produce four strokes (both cars and motorcycles) to guide them ......... except for one European company, with their fuel injected Two Stroke enduro model, but we will have to wait to see the results of their efforts this year,

Unfortunately the words "Two Stroke" have now become dirty words and the latest attempts at revival are further hampered by many people seeing this as fact.

Frits Overmars

24th March 2017, 11:35

... legislators who only read the impressive graphs presented by certain domineering companies who produce four strokes (both cars and motorcycles) to guide them...
Unfortunately the words "Two Stroke" have now become dirty words.There's a private forum called the2strokes. If I write 'Honda' there, the forum software treats that name as a dirty word and automatically changes it into H***a :whistle:

WilDun

24th March 2017, 12:15

There's a private forum called the2strokes. If I write 'Honda' there, the forum software treats that name as a dirty word and automatically changes it into H***a :whistle:

Goes to show that artificial intelligence is not quite there yet - maybe we need to invent artificial commonsense! On the other hand ..... we have invented another artificial thing, called "PC", ...... hope it's still PC to say "Honda" here!

YellowDog

25th March 2017, 11:20

apparently alcohol is good for your engine:

<iframe width="860" height="485" src="https://www.youtube.com/embed/jdW1t8r8qYc" frameborder="0" allowfullscreen></iframe>

tjbw

27th March 2017, 08:22

tjbw

27th March 2017, 12:53

husaberg

27th March 2017, 14:28

Someone mentioned BSA somewhere?

Here's a prototype 250cc near horizontal single. Features include 4 radial valves, 2 carbs, 2 exhausts, monoshock rear suspension. 'Management' decided not to put it into production.

It's on display at the National Motorcycle Museum near Birmingham, UK.

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

Grumph

27th March 2017, 18:42

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

They did - it's effectively a horizontal Goldie motor in a close copy frame.

husaberg

27th March 2017, 18:52

They did - it's effectively a horizontal Goldie motor in a close copy frame.

No GPR boys father was talking about doing one.

WilDun

27th March 2017, 21:24

guyhockley

28th March 2017, 09:07

If you want to supercharge an engine, you must blow through the port that closest last. In a four-stroke engine that's no problem, but supercharging a two-stroke tends to be less effective. You blow through the transfer ports, but when these close, the exhaust port is still open, so you cannot really create a high pressure in the cylinder.

Closing the exhaust port before the transfer ports was done in the pre-war blown DKW racers with their split-single layout and in the Jumo 205 uniflow engines
with a crankshaft at either end of the cylinders. But as supercharging was forbidden after the war, nobody seems to have given it much thought since then.

I knew that Motobecane had experimented with a DKW type engine, but I was looking through some books I was given in Belgium and discovered I have a manual for the production version!

329586329587329588329589329590329591

Bore and stroke are 39 x 41,8, balance/charging piston (the manual can't seem to decide which to call it) is 62 x 13, "as the stroke is so short, the cast-iron charging piston is very heavy to achieve satisfactory balance". It has a deep recess to reduce pumping losses, I assume that's the dotted line in the diagram.
Comparing it to the standard model with the same 13mm carb, that gives 2,10ch @5500, torque peak @ 3500.
Port timing: Exhaust 150 degrees standard, 127 degrees "blown".
Transfer 104 degrees standard, 92 degrees 20' "blown".
Standard motor is piston ported. No idea if the exhaust and/or silencer is different.
Text comments on this being a lot of work for such a small power gain, but explains that it's a moped with a legal top speed of 45kmh. Says this model has 50% more torque and similar fuel consumption to the rest of the range (330 - 370 g.ch/h).
So, not quite a DKW! I'm sure I've seen a picture of an experimental trials bike (Bultaco or Montesa?) using the same idea...

ken seeber

28th March 2017, 11:36

WilDun

28th March 2017, 12:00

I think it was Bultaco, but the pumper piston was at 90 deg to the engine cylinder bore, however I don't know what the phasing was. Possibly for a trials bike where they were chasing improved low speed torque.

Yes, that was a Montesa (I think Mr Bulto originally worked for Montesa)
Concentric pin layout (to me) seems to produce compatible phasing - with cylinders at 90 deg. (a little difficult for experimenting if you had to move the pump cylinder axis to change the phasing though!).

329604)

Pursang

28th March 2017, 19:45

Here's a little scooter, produced by Excelsior in 1942 and 1943, for delivery by parachute!

I guess they were easier to pack, than to ride off-road.

This is on display at National Motorcycle Museum, near Birmingham UK.

My First motorcycle, built around the mighty Villiers Junior Deluxe. :first:

https://s3.amazonaws.com/WEBPOSTS/OZVMX/Number+1+%26+Number+2.jpg

Sorry, You'll need to click the link, the insert image box doesn't like the URL ???

Niels Abildgaard

28th March 2017, 20:05

Yes, that was a Montesa (I think Mr Bulto originally worked for Montesa)
Concentric pin layout (to me) seems to produce compatible phasing - with cylinders at 90 deg. (a little difficult for experimenting if you had to move the pump cylinder axis to change the phasing though!).

329604)

Two strokes are only for ships,mopeds and chainsaws.
Mopeds and saws have noise and vibration problems.
Balance from a V2 scheme is almost perfect.
Noise is a big problem.
Let us divide the Exhaust in two ports one over the other.
The upper exhaust port can be connected to the unused frontchamber of the pumping cylinder ,that sucks and contain the violent blowdown and noise.
The lower port goes to athmosphere without to much hindrance.Very compact but I need to find a material that will be able to act as exhaust outlet reed valve for the pumping cylinder front.

WilDun

28th March 2017, 20:28

Balance from a V2 scheme is almost perfect.
Noise is a big problem.........
Let us divide the Exhaust in two ports one over the other.........

Maybe the pump could also suck in a little air as well, to use up the rest of that unburnt mixture we are always hearing about and also produce power (to some degree)!

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 :msn-wink:).

PURSANG, wasn't that little bike called the "Corgi" - they used to drop both them and the Royal Enfield RE1 (with its DKW inspired engine) to the troops in Europe.

husaberg

28th March 2017, 20:34

I think it was Bultaco, but the pumper piston was at 90 deg to the engine cylinder bore, however I don't know what the phasing was. Possibly for a trials bike where they were chasing improved low speed torque.

I drew up something similar 20 years ago i had the crankpin phased at from memory 90 degrees and the v 90 also. (It might have been 45 degree phasing)

I think the idea was to have a large crankcase but normal primary compression.
The layout was similar to the piston supercharged DKW but the timing was different (from memory anyway?)
It had coloured felt pen an all.

329615329616

I knew that Motobecane had experimented with a DKW type engine, but I was looking through some books I was given in Belgium and discovered I have a manual for the production version!

329586329587329588329589329590329591

Bore and stroke are 39 x 41,8, balance/charging piston (the manual can't seem to decide which to call it) is 62 x 13, "as the stroke is so short, the cast-iron charging piston is very heavy to achieve satisfactory balance". It has a deep recess to reduce pumping losses, I assume that's the dotted line in the diagram.
Comparing it to the standard model with the same 13mm carb, that gives 2,10ch @5500, torque peak @ 3500.
Port timing: Exhaust 150 degrees standard, 127 degrees "blown".
Transfer 104 degrees standard, 92 degrees 20' "blown".
Standard motor is piston ported. No idea if the exhaust and/or silencer is different.
Text comments on this being a lot of work for such a small power gain, but explains that it's a moped with a legal top speed of 45kmh. Says this model has 50% more torque and similar fuel consumption to the rest of the range (330 - 370 g.ch/h).
So, not quite a DKW! I'm sure I've seen a picture of an experimental trials bike (Bultaco or Montesa?) using the same idea...

That layout looks like the DKW ORe engine

1928

https://www.youtube.com/watch?v=r3HXCk0bWiE
https://www.youtube.com/watch?v=seZUgOt_fww
https://www.youtube.com/watch?v=75WaFWR2qrA
329622
http://4.bp.blogspot.com/-h8s_uWPOwxY/UvmJ6aCi5zI/AAAAAAAAEaY/25ZDTRl6epE/s1600/DKW+ARe+ORe+engine.jpg

329620329619329621
http://www.odd-bike.com/2014/02/dkw-supercharged-two-strokes-force-fed.html

Pursang

28th March 2017, 20:59

https://s3.amazonaws.com/WEBPOSTS/OZVMX/Extra+pressure+exhaust+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.

(In the real world, (wherever that is), it will undoubtedly need asymmetric timings or different strokes or electronic control, or something) :bleh:

cheers, Daryl

Pursang

28th March 2017, 21:10

PURSANG, wasn't that little bike called the "Corgi" - they used to drop both them and the Royal Enfield RE1 (with its DKW inspired engine) to the troops in Europe.

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.

Frits Overmars

29th March 2017, 00:18

https://s3.amazonaws.com/WEBPOSTS/OZVMX/Extra+pressure+exhaust+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 :D.
329644

tjbw

29th March 2017, 02:39

Haha, nice find Daryl! This was my design in 1975 for a 180° parallel twin :D.
329644

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

29th March 2017, 02:58

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

29th March 2017, 03:45

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/motorbikes/2715939/A-thoughtful-genius.html

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