Ground connection in the front

[WGuaire]

I'm connecting a battery voltage display on top of the instrument panel. Also, I'll be attaching 2 x 10w driving lights up front. What's a good place to attach the ground? Where's a ground connection that won't overload the 10 AMP headlight circuit?
Cheers,
Bill

[jefferson]

One of the coil mount bolts would work. If I remember right the harness has a ground point there also.

[WGuaire]

One of the coil mount bolts would work. If I remember right the harness has a ground point there also.

The fairings are off now. I'll be able to take a look at that mount bolt. I'll check it for ground with my Pilot Probe III. It makes me look like a smart guy!
Thanks, Jefferson

[kevin g]

I would recommend running the ground wire back to the battery.  The standard practice of grounding the battery to the engine case and then attaching a ground wire for the harness somewhere on the frame is poor electrical design.  All of the return current of the electrical runs through the harness, to the frame ground point, through the frame to the engine (at the mounting bolts) and the to the battery from the ground wire.  All of this current path is very long and current flowing in dissimilar metal interfaces can be bad news for corrosion problems.

I ran a 10ga. wire from the battery to the same coil mounting location as the harness ground so now the least resistance path is through the wire.  If you want to get real carried away install a terminal block and tie all of the grounds there but do retain a harness ground to the frame as well.  Or, just add a bolt somewhere on the frame that you tie all of the grounds to.

Adding this ground wire on my vision and my 1988 BMW R100RS improved the electrical system a lot.  You will find less voltage drop in the system if you add the ground at the battery.

[WGuaire]

I would recommend running the ground wire back to the battery.  The standard practice of grounding the battery to the engine case and then attaching a ground wire for the harness somewhere on the frame is poor electrical design.  All of the return current of the electrical runs through the harness, to the frame ground point, through the frame to the engine (at the mounting bolts) and the to the battery from the ground wire.  All of this current path is very long and current flowing in dissimilar metal interfaces can be bad news for corrosion problems.

I ran a 10ga. wire from the battery to the same coil mounting location as the harness ground so now the least resistance path is through the wire.  If you want to get real carried away install a terminal block and tie all of the grounds there but do retain a harness ground to the frame as well.  Or, just add a bolt somewhere on the frame that you tie all of the grounds to.

Adding this ground wire on my vision and my 1988 BMW R100RS improved the electrical system a lot.  You will find less voltage drop in the system if you add the ground at the battery.

kevin g - Sounds right. Having a boat in salt water is not the same as fresh water. It's the electrolysis!
  I am in the process of routing my wiring to an Eastern Beaver PC-8 fuse block. It has two un switched circuits. One of them is a 12v cigarette style socket attached to the handlebar. I will tap into its ground wire and send a connection just aft of the headlight bucket to collect the ground circuits of my low draw voltage meter and the higher draw LED driving lights. I will let the regular ground side wire of the 12v socket go back to the ground on the PC-8. The PC-8 wires directly to the battery.
  I will be mounting switches and sockets directly into the fairing and sending the wires back to the PC-8.
  I have replaced the H4 with a a superbrightLED H4.
  The regulator/rectifier has been replaced with a MOSFET from roadstercycle.com.
  Overall, I'm attempting to make the sport bike Vision, into a sports touring motorcycle. My '83 has what I consider to have the best sports/touring bike fairing/windscreen ever made by a factory.

http://easternbeaver.com/Main/Wiring_Kits/Fuseboxes/PC-8/pc-8.html

http://roadstercycle.com/

[kevin g]

I would still recommend adding the ground wire from the battery to the point where the wiring harness connects to the frame, that will help the stock electrical system have lower voltage drop.