Air compressor to gas engine

curtisfox

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Maybe it's a 2 stage compressor, first cylinder puts charge to second for the fire............Curt
 


Will'smotobikes19

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So mechanical fuel injection? So like a car that doesn’t run on all cylinders. He said it goes 20mph or whatever probably wouldn’t go as fast as a single cylinder compressor engine and a gravity fed carberator. Cast iron block too. Don’t know what the advantage of a cylinder forcing gas is. That pipe is long that comes off the dummy cylinder. My 3hp Briggs would probably beat it in a race and it’s governed and has a large rear sprocket. That rpm sounds as if it was barely running maybe 450rpm. If you can engineer one of these properly I’m sure it would be worth it if the thing was free. I wonder why he didn’t attempt to use both cylinders for power? Unless the pistons are at different positions than a 4 stroke vtwin. With a 49cc or even lower displacement engine 22mph can be reached and those are much lighter. What would be cool is if someone made a 79cc engine into a vtwin.
 
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RocketJ

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Dec 2, 2017
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So mechanical fuel injection? So like a car that doesn’t run on all cylinders. He said it goes 20mph or whatever probably wouldn’t go as fast as a single cylinder compressor engine and a gravity fed carberator. Cast iron block too. Don’t know what the advantage of a cylinder forcing gas is. That pipe is long that comes off the dummy cylinder. My 3hp Briggs would probably beat it in a race and it’s governed and has a large rear sprocket. That rpm sounds as if it was barely running maybe 450rpm. If you can engineer one of these properly I’m sure it would be worth it if the thing was free. I wonder why he didn’t attempt to use both cylinders for power? Unless the pistons are at different positions than a 4 stroke vtwin. With a 49cc or even lower displacement engine 22mph can be reached and those are much lighter. What would be cool is if someone made a 79cc engine into a vtwin.
This engine design isn't supposed to be high hp. He explained that it has a ton of bottom end torque so even though it wouldn't win any races, it probably has good mpg and can trudge up hills with ease. I'm very tempted to give this a try. I just don't know what else is needed besides a stock compressor, a carb and a spark plug. Any ideas?
 

Will'smotobikes19

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It’s weird because I didn’t see any valves ontop the power cylinder and the spark plug was way on top that fitting could it be possible he’s using the stock compressor valves?. I would find a way to use 4 stroke valves and pushrods. It’s probably easier to convert a vertical shaft engine to horizontal. Timbone did that I think.
 

RocketJ

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Dec 2, 2017
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It’s weird because I didn’t see any valves ontop the power cylinder and the spark plug was way on top that fitting could it be possible he’s using the stock compressor valves?. I would find a way to use 4 stroke valves and pushrods. It’s probably easier to convert a vertical shaft engine to horizontal. Timbone did that I think.
I don't see why the reed valves that come with it wouldn't work. 2 strokes have reed valves and they work fine.
 

RocketJ

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Dec 2, 2017
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So I'm only a few short weeks away from starting the compressor engine build. My main concern right now are the valves. I've looked over diagrams as much as possible and I'm starting to agree that the stock reed valves may be too weak to handle combustion, so here's an idea. What if i strip out the valves (as simple as removing a gasket) and merge a 2 stroke reed valve to the cylinder head? It's built for combustion and doesn't require any extensive work like a push rod system would. What do you think?
 

RocketJ

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Dec 2, 2017
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Not sure, but compressor are designed to hold a lot of pressure also. .........Curt
Yea I'm not sure either. This build will be my first real experiment. Either it works and i have a nice old looking v twin or i seize a compressor. The pressure isn't the real issue. My concern is whether or not the thin reed valves can withstand the actual combustion.
 
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