Battery not charging? Might be time to replace your rectifier or regulator, and why not replace them both at once with a part that will work better than the originals. This Rectifier / Regulator Combo will replace both your old rectifier and regulator. Unlike many other units, this regulator rectifier is designed to work with lead acid based batteries, including Gel batteries as well as lithium batteries. You must have a fully charged battery in perfect working order before installing a new regulator rectifier.
Dimensions: 82mm Long x 30mm tall x 80mm wide
Mounting Hole spacing - 66mm (measured center to center)

Replaces these Honda OEM part numbers: Rectifier: 31700-333-008 Regulator: 31400-300-035
We also carry a if you need to replace the rectifier connection on the stock wiring harness. If the stock connector is brittle and the terminals are corroded, it's best to replace it.
Note: The white 5 wire connector plugs into the stock wiring harness, replacing the old rectifier. The 3 male spade connectors plug in where the old regulator connected. Corroded / loose / damaged wiring is a very common cause for charging system issues, make sure all connections are clean and secure. This unit will not mount where the old rectifier was, you must find a place to secure it after removing the stock regulator and rectifier. The body of the unit does not need to be grounded.
Note: The regulator rectifier is not compatible with lithium batteries that require a constant set point voltage of 14 or higher.
CB350F - 1972-1974
CB400F Super Sport - 1975-1977
CB500K - 1971-1973 (1971 needs and replaced)
CB550F Super Sport - 1975-1977
CB550K - 1974-1978
CB750F Super Sport - 1975-1978
CB750K - 1969-1978
Designed to work with 3 phase charging systems on pre-1979 Honda SOHC4's
Will also work on the CB750A Hondamatic 76-78 but the plastic plug must be removed and swapped for an