Voltage Regulator for Honda CB650 Nighthawk CB750 CB900 CBX Super Sport CB1000 CB1100 Custom Four K Limited 1979-1985

This voltage regulator rectifier is made specifically for field coil control regulation applications. This type of system regulates battery voltage by turning the field coil in the electromagnet rotor on and off to control when current is produced in the stator. In this application it is absolutely critical that every piece of the system is working perfectly.

This includes:

• The battery, which must be fully charged and in good condition.


• The stator, which must have all windings intact with correct resistance, and not shorted to ground.


• The carbon brushes, which conduct current to the slip rings on the rotor, and must not be pitted, glazed, or broken.


• The field coil rotor, which must have the field coil intact with correct resistance, not grounded, with slip rings clean and smooth.

It is often assumed that this regulator is bad when replacing only some pieces of the battery charging system. In our testing, this product is extremely rarely the problem. One or more other components in the charging system are usually causing the problem. Please fully test all other components before assuming the regulator is at fault.

Battery condition is extremely important. No voltage regulator can work correctly with a bad or weak battery. Always fully charge your battery before performing any charging system tests or replacing parts. If there is any doubt, have the battery load tested or replaced.