The Bucket Foundry

[Flettner]

In fact its air cooled and the two carburetors add up to a 24mm throat, would I be allowed 110cc?

But it has oil cooling and more inlets than just the carburetors, so I guess back to 98cc.

[F5 Dave]

125 24mm if 'air' cooled.

[ceci]

My first thought was the method once used by Saab, with one electrode reaching down from the cylinder head and another electrode spike riding on top of the piston.

What is the ignition advance?
The spark jumps so far away?

[Flettner]

was a time when the two electrodes were touching, at time of ignition one electrode was moved away, causing a spark. A little before my time even.

[Flettner]

jet A1 acceptable?
Methane gas?
LPG?

[Frits Overmars]

What is the ignition advance?
The spark jumps so far away?

I expected such a reaction, Ceci. But the electrodes need not be in line; they can have a little offset, so they can be longer and pass one another on the piston's way up.

[Frits Overmars]

This engine should run fine on Kerosene or Diesel or Jet fuel.

Sounds bucket legal. . .

Bucket rulebook-legal, maybe. But I would not have such a contraption on my asphalt if I were a track owner. Dropping a diesel bike can put a circuit out of business for a considerable amount of time. Kittylitter may be useful for absorbing a few drops of spilled lube oil, but not for a gush of diesel oil.
On the bright side, no doubt Flettners new contraption will also run happily on gasoline or E85.

[Grumph]

jet A1 acceptable?
Methane gas?
LPG?

Frits makes a very good point about diesel....

Here in NZ there is a precedent for LPG. Mike Marshall won a Heatway rally with an RS Escort running on LPG.
Motorsport NZ gave him a waiver for that event to let him use it. It was supposed to be a "coming fuel" for race purposes.
That didn't happen but I'd reckon Motorcycling NZ would allow it if asked. They're a bit more open to alternative fuels now -
but still hamstrung by over-restrictive fuel testing regs.

[Flettner]

Its this with a few more holes in it, proper exhaust and much better control. Some have been interested as to what I'm up to. A reedless crankcase and a new head design.
https://youtu.be/TOHKls3Cxjs

[WilDun]

Ok Frits, just for you.
New my engine has no EFI or ECU or injectors, no reeds or rotary valve, no spark plug, no ignition system just two carburetors (ultimately one would do), KISS. BUT it is opposed pistons.
An ideal aviation engine maybe? My preasant engine (Subaru) burns one litre every three minutes, considered acceptable but it would be nice to do better on cheaper fuel.
This engine should run fine on Kerosene or Diesel or Jet fuel.
Idle speculation perhaps.
The unit I'm building at the moment displaces 98cc, has a clutch and gearbox attached, for road testing.
Im not wasting time on pattern work or casting just modifying an existing cylinder, I want quick results to tell me if I'm heading in the right direction.

Certainly it sounds better than attempt #1 - however, suggest changing the "manual " carb /throttle arrangement to a proprietary one! - when will the head details be laid bare?

[F5 Dave]

At least 70hp I'd claim if I were you.

That's pretty cool.

[ken seeber]

Some good stuff here:

Neils: The 235/250 gm/kWhr figures are very impressive, so is the relatively low weight. Do you think these are correct? If they are then they’re wonderful. Best of luck with your Junkerator, it looks very interesting.

Patrick: Your annular combustion idea is neat in that it allows good access for 1, 2 or even 3 spark plugs if considering SI. Key issues could be the higher surface area/volume ratio compared to a central bowl. Did a quick comparison model based on 50 bore and 15:1 CR. 4567 cc for a spherical central bowl compared to 6295 with the annular. Feel free to debate the dimensions used. See pic.



However I think the surface area would become less relevant when running HCCI

Husa: Ring of fire….good one.

Fletto: In your vid, were the speed fluctuations synchronized in any way to your spray gun (sorry fuel injection) applications?

Long live the two stroke…

[ceci]

I expected such a reaction, Ceci. But the electrodes need not be in line; they can have a little offset, so they can be longer and pass one another on the piston's way up.

His proposal was for the opposite piston engine, in that case the length is doubled. The electrodes would not be too long, which exposes them to easily deforming

[Frits Overmars]

His proposal was for the opposite piston engine, in that case the length is doubled. The electrodes would not be too long, which exposes them to easily deforming

I was not too fond of sending the ignition current through the crankshaft, big and small end bearings, or through the piston rings, anyway. Spark erosion can be a great tool, but you don't want it to happen inside a running engine. We'd better concentrate on HCCI.

[Flettner]

So long worthless reed block housing.