Some years ago, I flew ultralights, a 'Dactyl' to be exact. It had a 430cc Cyuna inline twin with a belt reduction. I think the reduction was 2:1 but I'm not positive. That thing put out tremendus thrust, and had a climb rate of 1000ft/min.I've always wondered why the larger gassers dont use a reduction drive in order to swing a bigger prop.
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