Weird engines 101
- Thread starter wfooshee
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bramfrank
BramFrank
Seems like they'd lose a fair amount of power through those rockers they use to drive the outer cylinders . . . .
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charismaticmegafauna
Well-known member
Oooh..., that's neat -- right in there with the 1939 DKW SS-350 5 piston, 2 sparkplug, 38 Hp twin cylinder motorcycle (Parallel-twin "twingle" + supercharger piston).
100+ Hp per liter isn't too bad for 1939 -- about on par with today's FJR...
100+ Hp per liter isn't too bad for 1939 -- about on par with today's FJR...
That is wild! Only 80 ponnies?
HotRodZilla
GOD BLESS AMERICA
That's exactly what I thought. All that time, money and effort to produce less HP than standard V-twins are making right out of the factories...Mass produced? Hmmmmmmmmm...
Ducati has always lacked in the HP dept. Although good usable HP is very good too. I like the power delivery of the twins.
ionbeam
2 FUN
I'm also in the 'missing the point' camp.
If the video is accurate to the design, this is a long stroke engine where the stroke is greater than the bore. It should be a smooth engine that makes good torque but would rev slower than a short bore engine. The article only mentions 80 hp. It could be 80 hp @ 200 lb/ft @ 2100 rpm. Paint that sucker green and yellow with a jumping deer. It could also be 80 hp @ 100 lb/ft @ 4200 rpm, at this point I would have to ask -- how fast does it rev? This would in part be related to the flywheel weight of the system. It could be 80 hp @ 50 lb/ft @ 8400 rpm, now the questions would be 1) is there a significant weight advantage over a conventional engine (I doubt it) and 2) if there is no power advantage, no weight advantage and it does not rev exceptionally quick -- why bother?
Looking at the show bike it appears that this configuration offers no air/fuel induction advantage. I see long narrow intake runners which would back the concept of a low revving, higher torque engine. Which leads us back to the logo for this bike:
It makes ya wonder what they are smoking thinking. Sometimes too much money and the engineering concept of -- because I can -- gets ugly. I'm interested to see what major hidden advantages they reveal at introduction.
If the video is accurate to the design, this is a long stroke engine where the stroke is greater than the bore. It should be a smooth engine that makes good torque but would rev slower than a short bore engine. The article only mentions 80 hp. It could be 80 hp @ 200 lb/ft @ 2100 rpm. Paint that sucker green and yellow with a jumping deer. It could also be 80 hp @ 100 lb/ft @ 4200 rpm, at this point I would have to ask -- how fast does it rev? This would in part be related to the flywheel weight of the system. It could be 80 hp @ 50 lb/ft @ 8400 rpm, now the questions would be 1) is there a significant weight advantage over a conventional engine (I doubt it) and 2) if there is no power advantage, no weight advantage and it does not rev exceptionally quick -- why bother?
Looking at the show bike it appears that this configuration offers no air/fuel induction advantage. I see long narrow intake runners which would back the concept of a low revving, higher torque engine. Which leads us back to the logo for this bike:
It makes ya wonder what they are smoking thinking. Sometimes too much money and the engineering concept of -- because I can -- gets ugly. I'm interested to see what major hidden advantages they reveal at introduction.
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Kinda neat, but the link on that page to this
5-axis milling machine demo is way cooler.
That thing could probably do vasectomies - fast.
5-axis milling machine demo is way cooler.
That thing could probably do vasectomies - fast.
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Good point ionbeam. I think it's more of the development and radical change of the rod and piston concept, which I think is a great idea in concept but may lack in functionality. You're right the fuel delivery system etc looks old and poorly thought out. They still aren't done, I'd guess because of issues like this.
Reminds me of the old McGee motor from Australia. They had a DOHC motor they introduced for drag racing back in the early 80's. The motor was never dialed in well and always broke. There maybe no real substitute from shear HP from a blown top fuel motor then the old piston over head valve, piston & push rod motors. The Wankel Rotorary engine, a very good design and idea, neat motor, but it never took off either, except with Mazda.
This is a neat concept, would probably work, but not very functional for performance and weight savings. I see it going the way of the Dodo.
Reminds me of the old McGee motor from Australia. They had a DOHC motor they introduced for drag racing back in the early 80's. The motor was never dialed in well and always broke. There maybe no real substitute from shear HP from a blown top fuel motor then the old piston over head valve, piston & push rod motors. The Wankel Rotorary engine, a very good design and idea, neat motor, but it never took off either, except with Mazda.
This is a neat concept, would probably work, but not very functional for performance and weight savings. I see it going the way of the Dodo.
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charismaticmegafauna
Well-known member
party pooper.
The sound that "125 Four" minibike makes KILLS me
This is giving me a headache:
Those engines start-off as 4 strokes. If the definition of a 4 stroke is based on # of crank revolutions per combustion stroke, then what would you call these?
EDIT: nah, it's still a 4 stroke... more like a pair of 4 strokes
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wfooshee
O, Woe is me!!
I'm still not real clear what's inside those inner pistons. The short conrod to the rocker arm has to pivot parallel to the crankshaft, but the attachment to the real conrod pivots across the crankshaft. Are there two wrist pins, or a u-joint, or what? How long will that last? Does it hold heat funny?
And like Ionbeam, I still don't see any "why" in this thing. And why call it a V-8? Each bank is a T-4, so it's a dual T-4.
And like Ionbeam, I still don't see any "why" in this thing. And why call it a V-8? Each bank is a T-4, so it's a dual T-4.
Crash Cash
Well-known member
Well, I haven't seen a really different engine concept come down the pike since Honda's oval pistons. It could be a dog or it could actually end up having some weird property nobody predicted. That's why you build one and find out.
Me, I think it's going to break a lot of those central conrods, because the force of a V-8 is going through 2 rods instead of 8. It's going to need to be pretty beefy.
Oh ****. They'd never get me away from the CAD station. I'd probably end up starving to death standing in front of it watching it run. I wonder how long it took?
MotorToad
Well-known member
It's never transmitting more than one little cylinder's worth, and that cyl's torque's being slightly absorbed by compressing another cylinder at the time. I don't think that'll be the biggest problem the engine faces.
DonRed7
Well-known member
You do realize that based on the design that the second firing pair is transfering power by pulling up on the crank rather than just downward as in a typical system. Throw stuff at me if i'm wrong or pointing out the stupidly obvious...
Cheers
DB
Cheers
DB
