125-200cc No spark

I put my bike away last sunday and it was fine i took it out this morning and it would start and run for a few seconds then cut out it did run for 30 seconds then it cut out i put a new plug in but still would not start so i got another new plug out put the ht cap on and put the plug on the head bolt and cranked it over but no spark i tried another coil but still no spark can anyone help thanks