recently i have aquired a 1981 yamaha sr185 exciter. the problem is you can sit on the starter button all day and the engine will turn over and even spark(i know b/c i got one of those blinky plug caps) but will not fire. now the crazy part is if I hold the starter button down and use the kill or ignition switch to start the bike it will start right up and run almost every time. I dont think its the switches as i have checked both with a meter. I have heard of similar problem involving rectifiers and regulators but i dont know how to check em. any ideas anyone?