It may be a 2 stroke motor that's been run on straight fuel and it has had its rings badly worn due to no oil in the fuel and squeezed the rings into the groove with no movement in them being able to spring back to the bore, thus absolutely no compression. Sadly this happens rather regularly and it's why many users get rid of non working two stroke machinery. Sadly if this is the case its all over for that bore, piston and rings.

I feel you should investigate this before you go much further, alternatively you simply might have a faulty decompression valve that is staying open, thus no comp at all.

Cheers,
BB.

I live a 24 Hour lifestyle, but every now and again I seem to fall asleep, well at least that's what my wife tells me.