ESE's works engine tuner

[adegnes]

That top reed block is quite high up the cylinder, looks like it goes straight into the back of the cylinder at transfer height, ie straight into the transfers.

I've been playing with the idea of a cylinder with short runners inside a plenum around the bore in place of the regular vertical transfer passages, hope this is something similar - would make me feel kinda smart.

[ken seeber]

Well, I reckon the cylinder is pretty much the same as a standard VM (see http://www.magtune.com/magtune/VM_MOTOR.html), but with the addition of a reed block which is very much the same as a Rotax Max and some early Kawasaki 125 motocross engines. This certainly dumps into the base of the B & C passages.

I've been playing with the idea of a cylinder with short runners inside a plenum around the bore in place of the regular vertical transfer passages, hope this is something similar - would make me feel kinda smart.

Going on to Adegnes's suggestion, there was a bloke on pit-lane last year who posted this:

“There was an engine in the 1930s called the Petter Harmonic engine. A low rpm engine that had the exhaust valves in the head and a long resonant length pipe. Can be seen via Google.

To me there are 2 options for the next quantum power jump in performance 2 strokes:

1. A ring of exhaust ports around the bore with valves in the head, maybe even passive reed valves, cooled each time during induction

2. Go with a RSA type port layout, but have a diversion valve, say in the B ports that allows this to be connected to a short (throttled?) duct from atmosphere, ie direct inlet to the cylinder, bypassing the crankcase. Even the diversion valve could be eliminated by simply dedicating the B port to external air (& fuel?) only, leaving the A & C ports to provide sufficient flow for starting and getting up to the tuned speed when the B port passage could be opened”

[husaberg]

I thought I had cracked it with the cupped piston but now can see it will not work with out a sleeve valve controlling the ex.
Left field But I feel the cylinder is very different with a sleeve valve shutting the exhaust port on the rise to tdc and opening it on the fall to BDC.
That is assuming it is "cylinder" supercharged.

Ken as for two stroke like engines with Valve I think this is pretty cool

Bourke engine

[ken seeber]

Husa, I reckon that the only way for a high performance exhaust to work is to have rapid opening, such as the piston in the bore (ie conventional stuff). Any poppet valved thing just cannot get the opening rate anywhere near that of the piston. The Petter thing was just old stuff, the point it was raised was the fact that an engine could run without passing air through the crankcase. Sleeve valve engines might be able to show advantages, but I think they will be thermally limited, ie poor piston cooling.
I guess we'll just have to wait.

[husaberg]

Husa, I reckon that the only way for a high performance exhaust to work is to have rapid opening, such as the piston in the bore (ie conventional stuff). Any poppet valved thing just cannot get the opening rate anywhere near that of the piston. The Petter thing was just old stuff, the point it was raised was the fact that an engine could run without passing air through the crankcase. Sleeve valve engines might be able to show advantages, but I think they will be thermally limited, ie poor piston cooling.
I guess we'll just have to wait.

My little mussing was based on it only shutting on the upstroke it would be normal on the opening of the ex.
I was trying to get it to work in my head for the last two weeks with two separate ideas that were in an old KG Draper book.
with the New engine why wait?
Do as I did and look at the link you provided and search the patent application this morning.
you need to just search the numbers to see what is there. the original link did not work.
Pretty sure one of them even had drawings.....
I must admit to only skim reading it and I have reputation for being a little slow.
Its bloody wordy
http://www.google.com/patents/WO2013185802A1?cl=en




Never noticed these before
NSR500V the 500 twin Below the reed intake?

[ken seeber]

Well done. The sumobrain link didn't work for me yesterday. Yep bit of reading required.

[breezy]

Took the Ryger-kart for a little spin today.
God Almighty!
Attachment 312179Attachment 312180Attachment 312181

I've got a fairly good idea of what to expect from a 125 cc kart. But this....
The revcounter could hardly keep up with the crankshaft but in any case it revved much higher than a normal 125 and I reached the end of the straight-away much quicker. What a rocketship!

seems like the hand over the spark plug , is placed as an obstruction , something behind ??

[adegnes]

Here's the iame m50 cylinder, got it a few days ago. It's so tiny it's ridiculous!




Meassured primary volume @tdc is about 242cc, will probably end up around 250-255 if I add material to the cylinder and match the ports to my case, or around 230-235 if I weld up the case transfers. Hmm... What to do?

[adegnes]

seems like the hand over the spark plug , is placed as an obstruction , something behind ??

What I'm thinking to...

[Grumph]

Do as I did and look at the link you provided and search the patent application this morning.
you need to just search the numbers to see what is there. the original link did not work.
Pretty sure one of them even had drawings.....
I must admit to only skim reading it and I have reputation for being a little slow.
Its bloody wordy

Well I think I see the air/oil separator...You may have cracked it husa. Doesn't mean that all the optional bits in the patent are actually on a race motor though, you'd only want the power producing stuff, the very green options can wait for a road motor.
I'm a bit dubious about the pumping diaphragm in a race engine...supercharging ?

[Flettner]

I've been playing with the idea of a cylinder with short runners inside a plenum around the bore in place of the regular vertical transfer passages, hope this is something similar - would make me feel kinda smart.

Good idea I think. Cast your own cylinder?

[adegnes]

Good idea I think. Cast your own cylinder?

Thanks! I want to when time/money/knowledge allows it, hopefully not in a too distant future.

[Frits Overmars]

Do as I did and look at the link you provided and search the patent application this morning...Its bloody wordy
http://www.google.com/patents/WO2013185802A1?cl=en

Don't bother deciphering that patent; it's not the Ryger-patent. The Ryger engine is much simpler.

[husaberg]

Don't bother deciphering that patent; it's not the Ryger-patent. The Ryger engine is much simpler.

Thank God........
I have pieced a few things together though.

We do not work with a high supercharging but create a balance between the upper and lower side of the piston, thereby, inter alia, there is less resistance.

Into a storage container
I have seen mention of Bellows or a bellowed chamber

Before the fuel-air mixture enters the transfer ports is the compressed once already.

into the separate chamber?

The ryger is no oil combusted which you have already made considerable gains.

separation chamber

Next point: your Aprilia consumed per revolution already sucked mixture volume of approximately 1.4 times the cylinder hold.
This was not due to the pumping action of the crankcase, but for the most part to the suction effect of the exhaust pipe. You remember surely have the test at Aprilia where a 52 hp engine, the exhaust pipe was disassembled. Then the ignition and carburetion were again perfectly tuned for the new pipe desperate situation, and the engine was measured again: 17 hp. A good pipe, the capacity thus tripling!
A sump pump can not, even if he pumped the double volume.

Also, the guiding of the piston is different so that the piston does not tilt.

Scotch Yoke

There is talk of 20,000 revolutions but in my first tile to find the exact information.
With Luc we find a good solution to limit the speed at about 20,000 rpm max is 30,000 at the moment.

Scotch Yoke

Indeed, we have a quick and clean stroke with an emphasis on clean and stroke is to keep alive.

Leads me to Scotch yoke again

Our 125cc has 70 hp at the rear wheel at 17,000 rpm and a maximum of about 30,000 rpm at 80% less ppm. HC certified by the civil service and now homologated cik fia

What does that knowledge from you is an additional pump to create space under the piston separated from the crankcase space.

Scotch yoke again

[speedpro]

Thanks! I want to when time/money/knowledge allows it, hopefully not in a too distant future.

I've thought of that as well. I was thinking of like a donut at a small distance from the cylinder fed by a supercharger and feeding ducts direct to the cylinder at the appropriate angles as now. My idea would be bulky but OK on a single. Crankcase or direct fuel injection of course.

Another thought I've had, about the 24/7 inlet, is that the 24/7 inlet does not have to be the regular reed inlet but could be additional. The little reed could feed the crankcase in some less preferred position and the 24/7 could feed the best location(s) seperately. Would require mamangement and fuel injection of course