I had an idea about building a gas powered quad. It would be powered by some of the new small 4-stroke engines like the honda gx-35.
I know what you're thinking... gas engines don't respond fast enough. But, everyone bases this on using the throttle and carb to control the power output. My idea is that in addition to the throttle you could use a microprocessor controlled CDI ignition to control the power.
With a microprocessor ignition you could immediately cut or reduce power output by skipping a spark for super quick power reduction and you could also retard the spark for a smoother, but still quick reduction.
At say 3000 RPM (typical) you could reduce power within 1/3000 of a sec by skipping a spark, or every other spark for a quarter sec or something of that nature. The throttle could also participate, but the spark control would be immediate.
I'm curious how a gas quad like this would perform. A Honda GX-35 puts out about 1.5 hp, and many sources say it easily turns a 20x8 prop at around 3000 RPM.
Would that be too large for practical use in typical applications? Each engine would be about 1.5 hp @ around 8 pounds (very lightly modified). That would be 6 hp @ ~32 pounds. I've also read that when the flywheel/magneto (using CDI) and clutch are stripped they can come in under 6 lbs. That would be ~6 hp @ 24 lbs.
I'd like to know if this is new territory or if someone has already tried this and what their results are. I haven't been able to find anything of the sort, so maybe it's a truly new idea.