Liquid error (layout/theme line 92): Could not find asset snippets/usf.liquid


  • Sale
  • Regular price $939.90
Tax included. Shipping calculated at checkout.

Introducing our newest heavy-duty recall-type charging system upgrade kit for Aprilia 2009-2020 RSV4 & 2011-2020 Tuono V4.

Anyone who rides or repairs Aprilia’s motorcycles is probably familiar with the stator, flywheel, and sometimes voltage regulator issues common to these models. Most of these bikes will have had at least one stator fail in their lifetime so far. The main problem was extremely strong magnets were used on the original flywheels, creating a very high power stator output, which generated excessive heat. This usually resulted in burned-up, or shorted stator winding, and often in a failed voltage regulator.

The solution was a new flywheel from Kokusan with lower strength magnets, dropping the stator output and heat generation. This results in a charging system output perfectly matched for the bike’s electronic needs and long-term reliability of the stator and voltage regulator.

To prevent or correct the flywheel problems, our engineers at RMS Labs have come up with a complete reliable heavy-duty charging system replacement kit for your Aprilia. Upgrade today if you haven’t already!

Included in this kit

  • Heavy-duty Kokusan brand recall-type OEM flywheel
  • Triple-tested heavy-duty stator
  • Flywheel puller

With this kit, you will be able to upgrade your current failure-prone charging system with a heavy-duty version using the latest technologies


Kokusan upgrade/recall type flywheel

Lower-strength magnets for correct stator output, low heat generation, and long-term reliability.

Built to OEM size

Fits precisely in your ride: install it and forget it.

Improved epoxy

Uses high-temperature epoxy that is stronger than OEM, eliminating the possibility of magnet detachment

High-grade steel capping

Prevents harsh additives in motor oil from degrading the epoxy attaching the magnets. Though extremely unlikely, if a magnet did ever come loose, it would remain in the sleeve preventing contact with the stator.

Precise balancing

Eliminates crankshaft vibrations for longer engine longevity.

Shop with confidence

All products are tested.

Don't waste time with temporary solutions, and start fixing your ride like a pro!

Stator Dimensions
Interior diameter: 43 mm
Exterior diameter: 105 mm
Thickness: 13.8 mm
Length of wires stator to grommet: 125 mm
Length of wires grommet to plug: 320 mm

Other specifications:
Number of wires: 3
Number of plugs: 1
Number of pins: 3

Wire to wire resistance :
Alternator : Between each Yellow = 0.3 ohms +-20%

Flywheel Dimensions
Exterior Diameter: 121 mm
Interior Diameter: 107 mm
Interior Diameter Center Housing: 19mm
Exterior Diameter Center Housing: 33 mm
Thickness (exterior): 35.3 mm
Thickness (interior): 30.65 mm

Flywheel Puller Specifications
36 mm x 1.5 right-hand male
Length: 60 mm
Exterior Diameter: 48 mm
Interior Diameter: 35 mm
Exterior Diameter Center Housing: 37 mm

Please note: There are two possible kits for RSV4 engine. This kit ONLY fits RSV4 engine numbers HIGHER than 3413 with KOKUSAN flywheels. Please compare our flywheel to your original.

If your RSV4 engine number is LOWER than 3413, your motor uses the Mitsubishi flywheel and will need Stator Assembly 857201. Refer to kit RMS900-104929.