My 1984 dr250s had a very weak spark swapped out with a different coil and still weak spark and took like 40 kicks to start cold but once warm started 1st kick, now it has cut out and has no spark. Ive fitted a new spark plug. Tested the trigger coil cold at 65ohms and hot at 93ohms Can any universal coil be made to fit like a 12v one? And ideas what it might be? Can i test the ignitor box? If so what tests?