RE: zdz 80b2rv engine
Does the choke plate have a hole or slight moon cut out of it? I so soldier it closed, that should help. After you modify the choke plate the way to start the engine is:
a. Close choke completely.
b. Open throttle half way.
c. Flip engine with ignition on until the engine coughs.
d. Take choke fully off.
e. Set throttle just above idle, flip until it starts, usually 3 to 5 flips.
Also, if the engine is hard to start, but runs great, you may be able to get it to start easier by richening the "L" needle a little.