I've had my Clipper II since Feb 04 and have 520+hrs on it.
I have never had problems starting it but know other who have had problems starting other machines with the same powerplant.
What I do:
cold engine:
mixture full rich
prime 8-10s
mixture full out
wait 30s
start it
quickly push mixture full in and apply cover
It should fire first time - this engine starts more easily when cold.
warm/hot engine:
mixture full rich (possibly crack throttle open slightly while priming)
prime 4-5s
mixture full out
wait 10s
start
quickly push mixture full in and apply cover
The engine needs to turn over a few cycles before starting when hot.
This works for me,
SB