My 1972 Tiger T100S 500cc will not restart, after initial start-up; i.e. only starting from cold: and will not restart once the engine is hot. It has electronic ignition & I have replaced the 6v coils, high output rectifier, HT leads & plugs, checked that the valve clearance’s are all correct, air filter, and stripped & cleaned the Mk1 Amal carb. But the bike remains unusable! Dose any knowledgeable person have any ideas of how I can resolve this issue?
Welcome Mr Woodcock 
Check the fuel supply is good, are the petcocks running ok and is the fuel cap vented. Try undoing the cap when it’s hot, if you hear a hiss…
If you are running the bike hot, summer temps, lots of traffic, running lean, then the petrol can vapourise in the carbs, again causing the engine to stall.
Check the output from the regulator by checking the voltage on the battery terminals (I assume you are running a battery). If the stator isn’t putting out the required AC then the regulator won’t be able to charge the battery. Some ignition systems rely on a good voltage to fire.
Batteries can lose capacity when hot so it may be the battery or a faulty ignition system. Take the plugs out and check for spark when the bike is hot.
Welcome and best of luck, let us know how you get on.
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Hi and welcome. Good luck in fixing your bike.