Stators & Magnetos
About Stators & Magnetos
The stator is a ring of coils fixed inside the engine's side cover. A flywheel with magnets spins around it, and that movement produces the electricity that charges the battery and powers the machine's electrical system. When a stator weakens or burns out, the battery will not stay charged, the lights dim, or the engine loses spark.
A bad stator is easy to confuse with a failed regulator or a tired battery, so test before buying. Your service manual describes how to check the stator's output and coil resistance. Stators here are listed by make, model and year, and the samples include year ranges for Honda, Yamaha, Polaris, Kawasaki and Arctic Cat models, so match yours carefully. A few listings also name a rectifier or regulator, so read the title. Replacing a stator means removing the side cover, so have the cover gasket ready too.
Brands include RM Stator, Moose Offroad and Rick's Motorsport Electric. Smaller parts for the same area are under Stator & Magneto Parts. The charging system also includes Voltage Regulators & Rectifiers, Batteries and Wiring Harnesses, Cables & Connectors, all in Electrical & Ignition Components.
FAQs on stators and magnetos
What are the symptoms of a bad stator?
Common signs are a battery that keeps going flat, dim or flickering lights, weak or no spark, and an engine that cuts out when the battery is low. A bad regulator or battery can cause the same symptoms, so test the stator output and resistance first.
What is the difference between a stator and a magneto?
The stator is the fixed set of coils, and the flywheel or rotor carries the magnets that spin around it. The word magneto is often used for the same charging and ignition assembly on powersports engines. Match your part by make, model and year instead of by name.
How do I know if it is the stator or the regulator?
Test both. The manual gives the stator's resistance and AC output at the plug, and the charging voltage at the battery shows whether the regulator is working. If the stator checks out, look at the regulator and rectifier next.
Do I need to replace the flywheel when I replace the stator?
Not usually. Inspect the flywheel for cracks, loose magnets and damage to the taper or keyway, and replace it only if it is damaged. Torque the flywheel nut to the manual's specification and use a puller rather than hammering.
