A brand new MOSFET voltage rectifier regulator for the Honda VT 750 and VT 1300 Shadow family. MOSFET technology is the answer to the classic problem with these charging systems: the unit runs cooler than all OEM diode style regulators, and it has overheat protection so that rather than burning up it simply switches off for a while and cools down. That single change removes the failure mode that takes out most original regulators.
It is a direct replacement for the original unit, plug-and-play and a direct fit, with a 90 mm square body, 30 mm height and 75 mm between the fixation hole centres, carrying 2 plugs and 5 pins. The heat sink and charging capabilities are improved and a higher grade of electric components is used, so the quality exceeds the OEM equipment. The unit maintains a minimum charging voltage of 14.5 V +/- 0.5 V, keeps the open circuit voltage under 15 V, handles up to 50 A / 500 W and operates from -20 C to 85 C. The opposite connector for the main harness side is included.
Key Features
- MOSFET design runs cooler than all OEM diode style regulators
- Overheat protection switches off and cools rather than burning up
- Direct replacement to your original unit
- Plug-and-play, direct fit, easy installation
- Improved heat sink and charging capabilities
- Higher grade of electric components
- Opposite connector for the main harness side included
Technical Specs
| Specification |
Detail |
| Part number |
RMS020-102324 |
| Type |
MOSFET voltage rectifier regulator |
| Width |
90 mm |
| Length |
90 mm |
| Height |
30 mm |
| Distance between fixation holes |
75 mm centre to centre |
| Number of plugs |
2 |
| Number of pins |
5 |
| Minimum charging voltage |
14.5 V +/- 0.5 V |
| Maximum charging current |
50 A / 500 W |
| Open circuit voltage |
Less than 15 V |
| Operating temperature |
-20 C to 85 C |
Vehicle Fitment Guide
Years shown are the overall coverage span for this part. Please confirm against the OEM part number on your original unit before ordering.
| Make & Model |
Years |
| Honda VT 750 (Shadow RS / Aero / Stateline / Spirit) |
2010-2024 |
| Honda VT 1300 (Shadow RS / Aero / Stateline / Spirit) |
2010-2024 |
OEM Part Number Cross Reference
Aftermarket replacement. OEM part numbers are listed for reference only.
| Part Number |
Manufacturer / Brand |
| 31600-MFR-671 |
Honda |
| 31600-MFE-641 |
Honda |
| 31600-MGR-671 |
Honda |
Frequently Asked Questions
Will this fit without modification?
Yes. It is a direct replacement for the original unit, with the same 2 plugs, 5 pins and 75 mm fixation hole spacing, so it is plug-and-play with no assembly required. Please confirm the OEM number on your original regulator against the cross reference table above before ordering.
What is included?
The MOSFET regulator rectifier, plus the opposite connector and pins for the main harness side so the plug can be renewed at the same time.
How can I tell my old regulator has failed?
Look for a battery that will not hold charge, a charging voltage at the battery terminals that never reaches about 14.5 V or that rises above 15 V, lights that dim or brighten with revs, and a regulator that becomes extremely hot. Burnt or melted connector pins are a strong sign the original diode unit has cooked itself.
What is the advantage of MOSFET over the OEM regulator?
A MOSFET regulator runs cooler than all OEM diode style regulators and includes overheat protection: instead of burning up under sustained load it turns off for a while and cools off, then resumes. Combined with the improved heat sink, that is why it is a durable upgrade rather than a like-for-like repeat of the original failure.
Dispatched from the UK · 12-month warranty · Fitment support from our technical team
