Headlight Relay malfunction

[ExcessiveBiker]

For about a year, I got an intermittent failure of the of the headlight to come on after starting. This past week the problem has become chronic. I have to repeatedly restart the bike to get the lights to work. This morning, I finally got the headlight on and left for work. Down the road I tried to switch to high beam, and the headlight quit entirely. Pulled over and went through the multiple starting sequence to get it lit again. This is a real pain in bad weather or very dark night. Any info out there?????

ExcessiveBiker

81H
81SH
80MNS
76XS750 original owner

[bikerphil]

Either take the relay apart and fix it, or bypass it by unplugging and jumping red/yel and blu/blk in the harness plug. Headlight will now come on with the key on. The relay is located under the fuel tank in front above the ign. coils with a 4 wire harness plug.

[BA80]

Bypassing it is best in my opinion. The light just comes on with the key then.

[IanDMacDonald]

I guess I feel dumb for not knowing this. I knew of the RLU bypass (which I know the PO did), but I never knew one of results of the RLU bypass was headlight on when key on. When I considered the HID upgrade, this bothered me, as it is advised to have the headlight off during start-up to reduce wear on the ballast (thus my question of using a '78 on/off switch). So, I'm curious: does the '78 have a RLU? And, if so, can you still switch the headlight off at start-up with the RLU mod on a '78? Also, why is it that you could turn the headlights on/off during riding on a '78 750, but not on a 1100 as you claim?

[crazy steve]

The RLU and the headlight relay are two separate things; bypassing one doesn't affect the other. If your RLU has been bypassed but your headlight comes on with the key, that means the relay has been bypassed also...