Join Date: Mar 2010
Location: Michigan, near Ann Arbor
The running lights (turn signals being on) should not affect things that much.
The other extra lights might, depending on what they are. I would suggest turning them off while testing.
13.4 is a bit low but not having the specs for that model, its hard to say. I've seen some bikes that routinely make 13.8 as their max voltage.
Its a hard call. Have you asked Shadow Shack? He visits here from time to time and is a regular on Duke's board.
1987 CMX250C Rebel
2002 FSC600 SilverWing
1983 Yamaha Midnight Virago XV920MK
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