Re: Compression too high.
To use a drill/socket you'd have to spin the magneto side. Here's where you can get into trouble especially with high compression. The crankshaft where the magneto rotor nut threads on is only 8mm, about 5/16". It is known that trying to pry off the rotor incorrectly can actually damage the crank at the threaded portion. I've seen them bent and I've seen the threads strip from people overtightening the nut.
If you're having problems pedal starting the engine the compression might be too much for those threads. Easy does it.
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