ESE's works engine tuner

[lucf]

Nope, normal two stroke wouldn't work with supersonic port, because you would lose pulsing and extract intake charge to the pipe, without any way to return it. Close to sonic, yes.

Or maybe it could work timed right, but without the pipe supercharging effect. So, if you are not doing it, maybe you should give it a thought.

I see supersonic in my answer as a very fast flowing duct, no more.
In a Ryger it's far less critical.

[Jannem]

Jumping out of the Ryger discussion back to regular 2-strokes:

What could be achieved, If you could run properly timed (relative to trasfers) much smaller than norm exhaust port with massive mass flow capability, but would lose the pipe supercharging? Effectively you could expel all the exhaust, keep things cool and pull a vacuum to the cylinder with late transfer opening and more area available for transfers.

A bit like FOS engine without pipe effect and blowdown limitation, very little heat and charge contamination?

With reciprocating exhaust slide valve you could run also very straight and non-directional, efficient, transfer ports. Could use the 24/7 reed for intake to get it started.

Lot of torque down low, linear response, rev it to the moon, good efficiency, lean mixtures without heat issues, simple structure and after reading about it in the internet -public domain.

[Jannem]

I see supersonic in my answer as a very fast flowing duct, no more.
In a Ryger it's far less critical.

I don't know the specific capabilities and limitations of Ryger, but every IC-engine with regular exhaust port is limited in performance by increasing pumping losses and heat. How is the power output in the mopeds limited? -Exhaust restriction.

[lucf]

I don't know the specific capabilities and limitations of Ryger, but every IC-engine with regular exhaust port is limited in performance by increasing pumping losses and heat. How is the power output in the mopeds limited? -Exhaust restriction.

Yes Ryger also, but not the same !

Again "Ryger is not a normal 2 stroke!, so don't think in normal 2 stroke !!"

[husaberg]

I don't know the specific capabilities and limitations of Ryger, but every IC-engine with regular exhaust port is limited in performance by increasing pumping losses and heat. How is the power output in the mopeds limited? -Exhaust restriction.

[Jannem]

Yes Ryger also, but not the same !

Again "Ryger is not a normal 2 stroke!, so don't think in normal 2 stroke !!"

No need to shout or take it personal. My comment was not about Ryger or 2-strokes, but in general about IC engines.

As I said, I have very little knowledge about Ryger engine. If your design allows conventional exhaust area, that will not lead into escalating pumping losses and heat with the discussed power and rpm levels, meaning the improvement comes from the intake side and combustion, it's all good. Those are the available options in any IC engine AFAIK. Edit: And of course friction and other losses, also discussed by you.

There are many ways to skin a cat and improve existing technologies. And it's great that people are still innovating IC-engines even at the brink of mass use of the electric powered stuff.

[Jannem]

Just for general interest, Ford applied for a patent to supersonic carburetor in the 70's, which used shockwaves to atomize fuel for better distribution and combustion. I suppose emergence of EFI killed it.

https://www.google.com/patents/US4206158

[breezy]

Yes Ryger also, but not the same !

Again "Ryger is not a normal 2 stroke!, so don't think in normal 2 stroke !!"

hi Luc,.. so.. we can say that this engine has a linear moving piston with little or no side thrust on the upper piston part.... different from a normal 2 stroke yes ?

the crankcase is in no way connected to the bottom of the cylinder/barrel except via the oil way through the piston between the piston rings.. different from a normal 2 stroke yes?

that the lower ports beneath the piston feed the higher transfer ports above the piston under a higher pressure... not the same as a normal 2 stroke yes?

that the port roof angle of each transfer port is the same as a run of the mill rotax junior barrel transfer port 2 stroke yes?

the exhaust/ port plays no part in the power achieved by this engine.. unlike a normal 2 stroke?

if you cant answer all, i will understand

[Norman]

Maybe Luc will tell you/us that the flow into the cylinder is so violent when the engine comes into resonance that the mix will have problems escaping out through the exhaust?

///
the exhaust/ port plays no part in the power achieved by this engine.. unlike a normal 2 stroke?

if you cant answer all, i will understand[/QUOTE]

[Flettner]

So what is this all about? Even if someone were to guess the answer, Luc can't confirm anyway! Lose lose situation, and more likely guide us away from the important stuff.
Interesting that Luc keeps coming back to this thread. Perhaps we are a little more civilized than some other sites😊

[lucf]

hi Luc,.. so.. we can say that this engine has a linear moving piston with little or no side thrust on the upper piston part.... different from a normal 2 stroke yes ?

the crankcase is in no way connected to the bottom of the cylinder/barrel except via the oil way through the piston between the piston rings.. different from a normal 2 stroke yes?

that the lower ports beneath the piston feed the higher transfer ports above the piston under a higher pressure... not the same as a normal 2 stroke yes?

that the port roof angle of each transfer port is the same as a run of the mill rotax junior barrel transfer port 2 stroke yes?

the exhaust/ port plays no part in the power achieved by this engine.. unlike a normal 2 stroke?

if you cant answer all, i will understand

Only the last is not correct, I did write exhaustpipe undepended for the rpm, which is something else.
Ofcourse the exhaustport plays a part when it is about power, but far less when it is about rpm, may be even not at all.
We first discovered that when the engine runs smoothly to 30k unless the homologated pipe which is dedicated for max power at about 13k.

[breezy]

Only the last is not correct, I did write exhaustpipe undepended for the rpm, which is something else.
Ofcourse the exhaustport plays a part when it is about power, but far less when it is about rpm, may be even not at all.
We first discovered that when the engine runs smoothly to 30k unless the homologated pipe which is dedicated for max power at about 13k.

Luc, as you have reduced the rpm levels down to a lower figure , is this achieved by changes to the amount of fuel inducted or size of transfer ports?

[ken seeber]

Instead of all this frustrating & “getting us nowhere banter”, why don’t we all just put in, say $20 each, and buy an engine. Then give it to Wobbly to test. When it’s all over, irrespective of the outcome, put it into the Christchurch museum next to the Britten with a placard saying “????????”

I vote Husa as #1 coordinator, seems a trustworthy dude ...maybe a Gofundme page?

[Michael Moore]

Ken, do you folks down under use the expression "don't buy a pig in a poke?"

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

it seems to apply here.

cheers,
Michael

[husaberg]

Instead of all this frustrating & “getting us nowhere banter”, why don’t we all just put in, say $20 each, and buy an engine. Then give it to Wobbly to test. When it’s all over, irrespective of the outcome, put it into the Christchurch museum next to the Britten with a placard saying “????????”

I vote Husa as #1 coordinator, seems a trustworthy dude ...maybe a Gofundme page?

you do have to wonder why they are worried about secret squirel stuff i thought they had an international patent.

Ken, do you folks down under use the expression "don't buy a pig in a poke?"

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

it seems to apply here.

cheers,
Michael

https://en.wikipedia.org/wiki/Courtier%27s_Reply
We have that, plus the emperor new clothes in NZ anyway.
plus other bag variations mostly suited to Waimate