The RM30020 is a brand new voltage regulator rectifier for Honda sports and naked models of the early 2000s, covering the CBR 600 from 2003 to 2006, the CBR 900 and 929 RE and RR from 2000 to 2002, and the CB 900 F for 2002 and 2003. It is a direct replacement for the original unit, fitting plug-and-play with no assembly required. The quality exceeds the OEM equipment, the heat sink and charging capabilities are improved over the original, and a higher grade of electrical component is used throughout.
These machines run their regulators hard, and heat is what eventually kills them. This unit is rated at a maximum charging current of 50 A / 500 W with a minimum charging voltage of 14.5 V plus or minus 0.5 V, holds open circuit voltage below 15 V, and is specified to operate from -20 C to 85 C. The body measures 103 mm wide by 80 mm long by 33 mm high with 70 mm between the fixation hole centres, and it carries two plugs with seven pins across seven wires of 300 mm. Every unit is tested before it ships.
Key Features
- Brand new unit, a direct replacement for the original
- Plug-and-play, direct fit, no assembly required
- Quality that exceeds the OEM equipment
- Improved heat sink and charging capabilities
- Higher grade electrical components throughout
- Maximum charging current of 50 A / 500 W
- Minimum charging voltage of 14.5 V +/- 0.5 V
- Two plugs carrying seven pins across seven 300 mm wires
- 70 mm fixation hole spacing, centre to centre
- Every unit is tested before shipping
Technical Specs
| Specification |
Detail |
| Part number |
RM30020 |
| Width |
103 mm |
| Length |
80 mm |
| Height |
33 mm |
| Wire length |
300 mm |
| Fixation holes, centre to centre |
70 mm |
| Number of plugs |
2 |
| Number of pins |
7 |
| Number of wires |
7 |
| Minimum charging voltage |
14.5 V +/- 0.5 V |
| Maximum charging current |
50 A / 500 W |
| Open circuit voltage |
Below 15 V |
| Operating temperature |
-20 C to 85 C |
Vehicle Fitment Guide
| Make & Model |
Years |
| Honda CBR 600 |
2003-2006 |
| Honda CBR 900 RE / RR |
2000-2002 |
| Honda CBR 929 RE / RR |
2000-2002 |
| Honda CB 900 F |
2002-2003 |
OEM Part Number Cross Reference
Aftermarket replacement. OEM part numbers are listed for reference only.
| Part Number |
Manufacturer / Brand |
| 31600-MCJ-641 |
Honda |
| 31600-MCJ-640 |
Honda |
| 31600-MCZ-003 |
Honda |
| 31600-MEE-872 |
Honda |
| 31600-MEE-003 |
Honda |
Frequently Asked Questions
Does this fit without modification?
Yes. It is a plug-and-play direct fit for the original unit and needs no assembly. The mounting holes are 70 mm apart centre to centre and the unit uses two plugs with seven pins across seven 300 mm wires, so you can confirm the match against your existing part quickly.
What is included?
The voltage regulator rectifier unit, tested before dispatch. No assembly is required and it is supplied ready to fit.
How do I know my old regulator has failed?
Measure across the battery terminals with the engine running. A healthy charging system reaches a minimum charging voltage of 14.5 V plus or minus 0.5 V and stays below roughly 15 V. If the voltage does not climb above resting battery level the unit has stopped charging; if it runs well past 15 V the regulation has failed and the battery will be damaged. Discoloured or melted connector pins on the regulator plug are another very common sign on these Honda models.
Does one part cover all three model families?
Yes. Honda used the same regulator specification across the CBR 600, the CBR 900 and 929 RE and RR, and the CB 900 F within the years listed, which is why the OEM cross reference above spans several 31600 series part numbers. Match the number on your existing unit to that list to be sure.
Dispatched from the UK · 12-month warranty · Fitment support from our technical team
