I've owned V-Dub motors in cars and planes. Cars start so easily, gently; you hear it come into life. Aircraft engines are different because you can't keep turning the whole system over.
If all parameters are set correctly, and spark timing imho is vital, then a fairly gently throw of the prop should do it. If you have to work up a sweat with any engine, then one of the fundamentals is out of limits.
In the UK, apart from high summer it's actually difficult to over prime, and if you do - blowing out is very effective, but remember that max draw occurs with the throttle closed.
Also check which mag 'leads' If you start on one, don't just select the one the previous owner said, make sure the wiring and top dead centre make sense.
Given the right fuel air mixture, with a spark occurring at the optimum moment your engine cannot help itself but start. If it don't, then there are things you can do.
Happy swinging and remember - better to be called careful than Lefty!
Sir George Cayley