Understanding Stators - A Comprehensive Guide



Products Mentioned in this Blog and Video:

18 Pole Stator Upgrade Stator
18 Pole Ruckus Stator & Magneto For GY6 (QMJ157)

Magnito Flywheel Puller Tool
GY6 11 Pole Replacement Stator
GY6 / QMJ157 8 Pole Replacement Stator
QMB139 Replacement Stator

Understanding Stators - A Comprehensive Guide

In the world of motorcycles, ATVs, and scooters, stators play a crucial role in the ignition and charging systems. This guide aims to provide a detailed overview of stators, especially the GY6/QMJ157 models, including their functionality, testing procedures, and specifications.

What is a Stator

A stator is an essential component in a vehicle’s electrical system, similar to an alternator found in cars. It serves two primary functions: generating electrical power to charge the battery and producing ignition signals for the engine.

Structure of a Stator

  • Mounting: Stators can be mounted to a plate or unmounted, depending on the design.
  • Coils and Pickup:
    • The stator consists of charging coils (often in multiples of six, like in the example above) and an exciter coil.
    • The pickup coil is responsible for sending signals to the engine for ignition.

How Does a Stator Work

The stator generates electricity when the magneto, attached to the crankshaft, spins. It is crucial to understand the following components:

Component Function
Magneto Spins to generate current
Charging Coils Produce electrical charge for the battery
Pickup Coil Sends signal for ignition to the engine
Exciter Coil Supplies power to the AC CDI box
  • AC vs. DC Stators: A stator can be either AC (alternating current) or DC (direct current) based on its construction.
    • AC Stators may have a wrap over the coils.
    • DC Stators lack this wrap and connect directly to the battery for power.

Identifying Stators

Knowing how to identify different stators is essential:

  • They can have varying numbers of coils, like 6, 11, or 12.
  • Familiarity with the wiring layout is also critical for identifying function and compatibility.

Testing Stators

To ensure your stator functions correctly, testing is paramount. This section outlines the necessary tools and methods for testing, primarily using a multimeter.

Tools Required

  • Multimeter: Essential for measuring resistance and voltage.
    • O: Ohms symbol
    • VAC: Alternating current volts
    • VDC: Direct current volts

Steps for Testing

  1. Setup Multimeter:

    • Connect the black wire to common (ground).
    • Set on the lowest ohm setting for resistance testing.
  2. Ground Wire Check:

    • Identify the ground wire and check for continuity.
    • Ensure this wire’s integrity by avoiding any contact with yellow charging wires.
  3. Charging Coil Testing:

    • Each yellow wire from the stator must have the same resistance reading when tested, indicating proper function.
Test Expected Reading
Ground wire continuity Should show continuity
Yellow wire to yellow Should have same value
  1. Pickup Coil Check:

    • Measure the resistance between the grounds and the pickup coil wires. Typical reading should be between 130 to 160 ohms.
  2. Reluctor Gap:

    • Use feeler gauges to measure the gap between the pickup and reluctor. Specs typically range from 0.008 to 0.020 inches.

Advanced Testing for Exciter Coils

To encounter starting issues, you may also need to perform more specialized tests, such as checking exciter coils if you suspect no-start conditions:

  1. Voltage Measurement:

    • Set the multimeter to VAC and crank the engine while measuring the voltage from the exciter coil.
    • A reading of at least 50 volts indicates proper operation.
  2. Final Verification:

    • Recheck all the tests to ensure readings maintain the specified range for both AC and DC models.

Conclusion

Understanding and testing stators is vital for anyone looking to maintain or troubleshoot their motorcycles or ATVs. Would you like to delve deeper into any specific aspect of stators or charging systems?

Always remember: proper testing can save unnecessary repairs and effectively diagnose problems early on. By following these guidelines, you can ensure your ignition system operates smoothly and your vehicle remains in peak condition.

If you found this summary helpful, don’t forget to subscribe for more insightful content, and feel free to leave a comment below with any questions or feedback. Happy riding!

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