Had the same problem with the voltage drain this summer. I put a amp meter on the battery and it constantly was pulling 2 amps. I disconteced the voltage reg. and it went away. Tossed a ohm meter on the voltage reg and all four pins showed ground. Replaced the volage reg. and it never drained down again. Could also be the headlight switch grounding out. Electrical problems are always fun. Good luck.