Yeah Ive has similar problems in the past...
found out that the condenser cuts the ignition out when it gets hot if it is crook. The other thing I got caught with was a blocked breather hole in the fuel cap once....only found that one after much cursing
and walking away from it to come back and crack the cap to hear the air hissing as it was going in and seeing the tank expanding....
Condenser...cheap fix I reckon...
Edit: I think Grumpy has given a text book Condenser/Kettering ignition system run down on here somewhere from memory....?
