Mystery item

[Karnivor]

Hi all Im new to these forums as i just picked up my 77 gs750 2 weeks ago, im pretty knowledgeable with automotive mechanics but new to bikes... ive been going over the bike and the mechanical seems solid except a few sticky carb issues but they are in progress, the thing that is getting me confused is is what looks like a relay or switch mounted to the top of the front cam cover on the left side. the center black wire ran too the the battery positive post with a inline fuse and the white and green were just hanging there, i see no other loose wire to match too and i can't see it in the wiring diagram from my haynes manual or and other diagrams i find online. being the wire is not included in the harness it seems to me like a add on by a past owner. on the front is say made in japan 12v 15A and on the green side says "on" all markings are stamped into the case.

Has anyone seen anything like this or a guess what it might be for?

Thanks in advance.

 

[Cipher]

looks like a voltage reg or rectifier off an old very old truck I had

 

[fbody_mike]

Sure looks like a relay that was getting its ground through the case. My guess is added on and not factory for the reasons you stated, and going by its location, my first guess would be a kill switch with the switched end going to the coils. Or it could have been a horn relay used to drive a horn "bigger" than the whimpy factory one. Neat relay by the way, I do not know how long it would live being mounted to a hot buzzy motor bolt, the frame would have been a better choice.

 

[Steve]

Based on the wire colors, it's not stock.

My guess is that it's a relay for a horn.

.

 

[Redman]

Welcome to GSR.

Thanks for picture.
Certainly is non-stock. SOmething someone added, like you suspected.

................. the center black wire ran too the the battery positive post with a inline fuse and the white and green were just hanging there, .....

Well, then, what ever it WAS for, it AINT now.
I would say to remove it before that extra wiring on batt+ has a chance to cause you a problem.

 

[Karnivor]

Thanks for all your help its gone...

 

[Redman]

Thanks for all your help its gone...

Again, Welcome to GSR.

Do introduce yourself (usally in Owners section), maybe post pic of bike.