hot starts: part deux

so here is the call to all the tech guys on kzr. i have a 1980 kz750h1, i just reset all the valve clearances, changed the battery, checked the charging system, and changed the spark plugs. the bike is bored over to somewhere south of 800cc, has pods, and 4to1 exhaust. here is the problem: when cold, the bike starts right up and runs great. if once warm the bike is turned off it will not start again until some time has passed. it sounds like the starter is just spinning and not catching anything...if that makes any sense. it will not turn over at all when hot. but once cold it will again just fine. thanks for the help!

When the engine is warm the torque on the
starter is greater.Either the starter clutch
or pinion could be slipping.

get under the charging rotor and change the pieces in the starter clutch. 3 roller metal pieces are the culprit. they get flat sided and slip on the inner cylinder
it is called a sprag clutch also the bolt that holds the rotor needs a lot of torque! red lock tight and a 1/2 inch impact gun does the trick.