These instructions cover most of the Honda singles and twins from 1978 and earlier. Other makes may require different modifications or have different wire colors. This part replaces both the stock rectifier and regulator, those parts must be removed.
Pre-Installation:
- Isolate the charging issue before ordering parts.
- Confirm your model has a single phase charging system.
- Check that the alternator is putting out the proper amount of AC current and all the connections are clean and making proper contact.
- Battery must be fully charged and in top working condition.
Recommended Wiring Modification for OEM Stator:
To get higher constant AC voltage, permanently join both halves of the stator rather than having the switch at the handlebars (or the switch on the headlight on some models) turn on the extra current when the lights are on. This works on all of the 350 and 450 Honda twins. If you choose to do this mod we strongly recommend connecting the regulator rectifier directly to the wires coming from the stator. Tape up any unused stock connectors.
- White wire and yellow wire coming from stator - merge together
- Result = pink wire running to the regulator rectifier puts out more power.
- Light green w/red stripe wire coming from stator (neutral light switch wire) should be plugged back into the harness.
Wire Functions:
- Red = Power
- Green = Ground
- Yellow = Stator input
4 wire stock rectifier
- Remove stock rectifier and regulator and secure wires. Not all models have regulators.
- Plastic connector plugs right in where original rectifier was. Usually it’s easily accessible under the seat.
- Mount new part where the old rectifier or regulator was. The casing does not need to be grounded.
- If the connector on the harness is different use the included parts to replace the stock connector. (plastic 4 pin terminal + 4 male spade terminals included.)
3 wire stock rectifier
- Remove stock rectifier
- Mount new part where the old rectifier was. The casing does not need to be grounded.
- Use included wire with eye terminal to ground out the green wire on the regulator rectifier. Make sure to find a solid ground.
- Use Included terminal kit (plastic 4 pin terminal + 4 male spade terminals)
- Brown from old rectifier - connect to yellow on r/r
- Yellow from old rectifier - connect to yellow on r/r
- Red from old rectifier connects to red wire on r/r