Critique This 2 Stroke Design

I'll kick it off

This design doesn't seem to overcome one of the primary drawbacks to 2 strokes

the need to lubricate the piston pin & cylinder. This will be greatly complicated by using the crankcase for a blower

I have no idea of how what kind of material is going to act as both a valve & the top of the piston

I keyed in on the fictitious concept of "copy written". That's not the only thing wrong, but it will do for starters.

Looking at the animation

http://www.grailengine.com/index.php

, Well, I think that's just one equivalent of the same thing

Having flown model aeroplanes and ridden 2-strokes, watched the animation too.
What's the oil stopper ring doing? Increasing friction?

Reed inlet valves were great, but we still needed transfer ports. So, same as before, with an extra valve in the head.

2-strokes are dirty engines. Are they using water and ethanol injection to keep that piston valve clean?

What revs does it run at?

What's the lube? Or is this thing made of ceramic and Boron Nitride?

If I am not mistaken the crankcase is separated from the combustion area by the piston rings just like a four stroke.

The air travels through two tubes on either side of the piston.

The tubes appear to slide up and down with the piston sealing the air from the oil.

The air flows through ports in the piston around the piston valve and then into the combustion chamber.

I am not sure how they control the piston valve timing.

I assume they add larger counter weights to the crank to offset the increased weight of their reciprocating piston.

It will be interesting to see it run because they are getting 100 H.P. out of a 500 cc displacement.

http://www.youtube.com/watch?v=NieQKp9H_wI

well I figured we should do this here for the reasons you gave elsewhere

we could talk about the less than perfect corporate ethics of this start up

I tried to use the contact form, but it bounces

Garthh,

Same here. Doesn't exist.

"Who's fooling Who" I'm also into music.
That 2-stroke expansion box sound rings in my ears!

Do you believe this?

http://www.grailengine.com/

Gimme a six-speed Suzuki!

considering the strong armed tactics reported elsewhere, I can sum it up

lots of smoke

no fire

I've had a few different 2strokes over the years, it's hard to beat the simplicity & power [& the ring ding sound]

any time you have the intake air going through the crankcase you're going have oil mixed in

I've never seen a design where the piston pin has a sealed bearing [not to mention the crank], there's going to have to be oil

direct injection will minimize the amount of unburned fuel

There is some kind of servo to control the piston valve, probably similar to what would be used for variable valve timing

Maybe we can get together and make a happy engine.
Short stroke, big bore, high compression ratio, electronic ignition, multiple fuels. No lube, emitting only water (H2O) or hot air. Also, heated grips for the frozen hands. Seat for those behind, too.

"Ti's a long way from Zimbabwe."

We can call it Magneto. Attracts nothing, but great at repulsion.
When those points open, it's like a CD system! Derails anything.

The Deek was a blasphous car. More, another time.

Great, though. 3 cyl, 3 coils. Don't get a blowout in a rear-wheel though.

Regards, Junior.

The 2 cycle Detroit Diesel engines used prssure lubrication throughout.

Nice Bob, except a model 71, will consume in the neighborhood of a gallon of 40 weight every 500 miles, so it might as well have oil injection....

there have been some proto type 2stroke gasoline auto engines that had fairly low consumption, more like a quart every 1000 miles

All they have so far is an idea.............that's it. Oh, and a dream legal team. This video is kind of funny. They keep looking at each other for answers.

http://www.youtube.com/watch?v=JRVQQI7al-k

I also don't understand how they are going to run a two stroke without mixing oil and gas. Maybe I'm just missing it, but I see no form of lubrication whatsoever.

A bit harsh Guest - Why so?

Just because the interviewer wanted to talk plugs and the brand was every-other-word and he personally endorses them, in everything he owns - how could you possibly think this anything but legitimate unbiased information?

Tut tut

Kramarat awards you an asterisk for sarcasm!

Well...It seems that we now have the "Carven" and "Grail" spoofs hitting CR4. Has anyone noticed a potential trend? Steve - Rega451

If you watch at the start of the exhaust/compression stroke valve in the top of the piston opens briefly then closes. Why? You would only blow exhaust gases back into the intake journals which makes no sense. This is an obvious flaw to a "revolutionary" scam.

I think the 'valve' is just 'sprung' (like that aero engine) and due to 'exhaust scavenging', is having a little 'cross over purge moment'.

Though, I do wonder what its mass/inertia is, in terms of piston deceleration forces

There seems to be a cam mechanism to open the "Intake" Valve at just beyond BDC. What else would explain the inertial forces it has to overcome? Certainly not just precompressed air flowing past a reed valve. If this valve is to take compression and ignition forces, it can't be a reed. But if a cam, how to lubricate it? High Viscosity Oil? That would cause parasitic losses, but would solve the intermixing issue afore mentioned. I guess we will all have to go to Cobo Hall in April to get the real show.

I'm thinking it is a poorly done illustration that doesn't represent the actual operation, if indeed it does actually operate.

There isn't any other descriptive illustration associated with it like there is for the other functional actions and so I believe this corroborates my notion that it is just an illustration error, a lack of attention to details. That's certainly reassuring and makes me want to invest.

At least it doesn't operate on tritium at $30,000,000 per kilogram.

This is sorta funny. I've had many ideas over the years of redesigning an ICE. The Grail was not one of them, although I sorta like the concept. When I was at first reading the post of Dave Simpson, my immediate thought was Ferrari has already done that, a few more words later and I could see where he was going. Myself, I've been working on a self reliant rotating shaft system since I was 5 years of age. That was 50 years ago. I ain't done yet,(it ain't workin yet either) but, I will work on this till it works or I push daisies. Oh how sweet they are in the early SPRING!

As for the Grail, well let's just call it "Holy" and let the dream float on. I still like the concept, and yes, I can visualize the oil ports for the required lube, and yes I also see where lube would definitely be brought into the combustion chamber in 3 different areas, so there would be smoke. As for efficiency, I'll give it 56% at best. For the EPA rating. Well, Foget about it. Ain't happening.

This may be closer to the state of the art

http://www.orbeng.com.au/

Just a couple of things from your animation..I notice the inlet-valve opens quite some time = Degrees before TDC. this is during the exhaust cycle.. but I see no reference to the exhaust pulse in the inlet/induction or any method to overcome it unless of course you are compressing the inlet air with more pressure than would exist in the inlet port.. also is the swirl pattern generating enough movement to give a even spread of fuel vapour from what appears to be the single injector enough to justify three plugs..

Piston cooling might be an issue as you cant use oil spray on the bottom, and the intake charge is the only cooling I can see available. The intake valve must cool thru the piston also, or is it the other way around??