IT STARTS AND RUNS FINE BUT THEN WILL NOT TICKOVER. THEN CANNOT START AGAIN UNLESS LEFT FOR SOME TIME WHEN IT AGAIN STARTS EASILY. PLUG IS NEW AND GOOD SPARK.CARB CLEANED AND FUEL IN FLOAT CHAMBER WHEN IT STOPS.EXHAUST CLEANED.

GEOFF., July 2008

Id suspect the condensor or coil breaking down when hot.Does it still spark after stalling?

yan, June 2009

i realize this post is old, but i would like to give the actual correct answer! there is a part called the condenser in all of these old moby's. its part of the points ignition system, its tough to get to cause its under the crank case, but then its easy and cheap to replace! (i got mine for $3.99 at autozone from a 1968 camaro) this part goes bad because it is weak against heat and vibrations, and wouldnt you know it, they decide its a good idea to put it inside the spinning part of the engine! the hottest most vibrating part on the whole bike!. i recommend rewiring it so that its outside of the crank case. if you want a tutorial for that, find a good moped forum and ask for help, but if you just replace it how it already is, it should work fine for like 10 more years or so.

Shane, May 2009

the insulation on high tension electrical parts can break down when parts are hot. expansion opens up cracks and can let the spark track out somewhere different. sometimes is a big job to find out where. sometimes one by one replacement is the only way to find it.

george, May 2009

Tempremental 2strokes! Crankcase and top end compression is important on 2strokes. It could be that you are lacking a little of either or both.
Check head bolts are tight with no signs of blowing, cylinder base to crankcase ditto, and carb. flange joint is good.
You seem to have checked everything else (including fuel mix?)
Difficult (or non starting ) when hot can be caused by loss of compression due to wear on piston rings. Replacing rings, if necessary, should not be difficult if bore is undamaged. De-glase the bore though, or the new rings will never bed in.

Mr. Toad, July 2008