Not sure if this will help you - My 97 thunderace started blowing the low beam filament every 2 weeks or so. Either globe would blow while the other remained ok. High beams on both globes would still be ok. The cause was moisture getting into the main loom plug that is located inside the fairing (below the left hand grip). With some CRC and a very fine file, I was able to clean out the connections of corrison. No more problems since.