Join Date: Aug 2006
Location: Honolulu, Hawaii, America\'s Pacific Paradise
You may have blown a diode (to ground) in your regulator/rectifier. It will still charge on the other two phases, but discharge when sitting. Try charging the battery and then unplug the rect./reg and let it sit. If it doesn't then discharge, you have found the problem.
Or, if you have a Volt Ohm meter, disconnect the hot (+) lead from the battery, and with everything off, place the positive lead from the meter on the battery + terminal and the neg. lead on the battery + cable terminal. If you get a reading, you likely have a bad rect/reg.
Triumph old, Triumph new, any Triumph will do.