I've been starting Zenoahs by hand for 15 years , still have all fingers intact , I wear a welders leather glove , and make sure the ignition switch is off , open throttle to full rock the prop agaist compression until prime is evident ( Wet ! ) switch on the ignition cut off to ON , close the throttle to high idle or (open just a crack)make sure the aircraft is secure (Tied down)or a helper restraining it and have the prop set so that compression is at 11:50 and slap it hard thru compression , should start within 3 or 4 attempts.
if the engine is set up within factory specs.
I Have a 24 volt system and a Sullivan Dynatron and find hand starting easier!
its even easier if you have an electronic ignition usig the same basic procedure
Good Luck !!