1960 VBB 150
We built a new wiring loom from scratch so that I could add an air horn and route the new ignition switch into the existing right hand handlebar unit. I didn't want to add an ignition key to the classic lines of this bike so this was the most inconspicuous way to disconnect the wiring from the battery. Since this bike used a P200E engine I mounted a battery inside the left hand cowl which runs the rear light directly. I used a P200E rectifier to charge the battery and the entire system has been perfect for over 5 years.
The headlamb bulb now uses a P200E indicator bulb as it still needs to fit into the exisiting 6V headlight housing. I've now worked out a way to use a halogen bulb in the existing holder. See the VBA project lighting page.
To use the original VBB handlebar switch (above right) as an ignition /horn switch we had to use relays (above left) as the original switch would not take the current. Relays are basically small boxes that work as a automatic switches. When low current 12V power is put into the relay it triggers a larger switch which can handle the current straight off the battery to power the horn. See the wiring diagram for more information. The actual relay we used can be found here.
The diagram at the bottom of the page changes from a standard VBB wiring to a P200E battery system with no indicators. The kill switch is located differently from the original VBB as shown below. Also the headlight is always on and the rear light and brake light run directly off the battery once the ignition switch is set to "run".