Do they have a Sprag clutch ?...they are a 'servicable' part....never had one struggling as they Normaly just spin without engaging...but maybe the spring has become lodged in the 'fingers'(ratchets)...

Is the ignition trigger on the same generator flywheel. maybe it was knocked during failure or repair if the timing is too far advanced the starter could struggle. Perhaps put a timing strobe on and check timing when running. Just a thought if it was OK prior to failure

I'd like to know a proper description and of the fault. If the bike starts from cold ok and rides ok and behaves as expected all the time is it only when you start it when you drop it or when you park it hot?

When did you notice the problem, before stator problem after? t
the problem started after stator bolts came loose

When it's running what's the tickover like? tick over is absolutely fine

Is it only if you try to restart it immediately after stopping it that it plays up. If you leave it for say 15 mins or half an hour does it start ok? if I was to leave it 30 mins to cool down it starts fine

What is your hot start procedure? Full throttle no throttle pump the throttle? In gear or in neutral? neutral with no throttle....will not start it...if I give it 4-5 pumps it will eventually fire up

You say the starter stalls? What do you mean? Gets to tdc and struggles to go over, cranks slowly like a flat battery? Any noises from starter gear when starting? it cranks like a dead battery. no weird noises just seems to....stop the motor.

What's the exact model. I seem to recall S model had some evaporated fuel control piping. E model

Do you stop it on the kill switch or the key? Does the kill switch pop out ok when pressed to switch it back on. (Kill switch full of mud and not releasing properly may open the starter circuit but still be killing the spark!) use key to kill engine

Does it restart easier hot with the choke on? (If it does then that's either air leak or incorrect jetting.) yes it seems to start easier with choke when hot...but I cant understand how that effects the starter from turning at full pace

Does it restart with the throttle wide open. pumping throttle works

What does the plug look like? Lean (white) rich (black) oily, fuelly. Is it the correct plug make and grade? new plug correct make and grade light brown colour on tip

How easy does it bump start when it plays up? Straight away or a lot of distance? (This will rule out the starter if it takes ages to bump) if it fires straight up you may have a dud starter, unlikely as thing like this are under more load with a cold engine. haven't tried to bump it......never considered it

If a bike won't start/run it's fuel, spark, compression, valve timing and clearances. In that order. You can possibly rule things out on the basis it starts from cold and runs fine.
So I'd rule out spark and compression and anything to do with the starter. That leaves you valve timing clearance or fuel.
You say valves have been done and checked so check the cams are timed up right.
While you do that check and clean the carb carb and check for air leaks and split rubbers and pipes in the breathers and evap canister.

My money is on a split hose or rubber somewhere or split diaphragm in the carb or wildly out jetting. If as you say it starts and runs fine at all other times and starts immediately from cold.


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