Sory i reply to fast, my bad ! Your jet is to big but it nevr create such a thing like a engine that died each time his wheel touching the ground ... i think so.
Did you get out the two big gear just behind the clutch bell ? Because there a mecanisme that allow the engine to be free (or not on pedalstart).
It's the drive plate first gear (223 463) and he was fill with drive plate roller (209 063) ... look if they are all there AND if the G spring (223 121)is not broken... and if you have to much clutch oil you can revese the G spring, i never remeber in wich sens it's supose to be but there is one !