We have a 1988 Harley-Davidson FLTC 1340 Tour Glide Classic discussion and after the winter here in MI, my husband went out to start it, and she started right up. Then, got some snow,so waited a few weeks, and she wouldn´t start. We bought a new battery and new plugs, and she started right up. Couple days more of cold weather, and now she won´t start again. Any suggestions?