Performance AC CDI (No Rev Limiter) - GY6 50cc (139QMB) (Standard)

Performance CDI for GY6 50cc to 170cc Scooters

This Performance AC CDI is engineered for GY6-based scooters with 50cc to 170cc engines, specifically designed to replace the factory CDI. It provides an aggressive ignition curve and eliminates the rev limiter to maximize your engine's RPM potential. This makes it one of the key GY6 50cc scooter parts for tuning enthusiasts looking to improve performance.

Rev Limiter Removal and Ignition Timing

This CDI unit features a retuned ignition timing map that boosts acceleration and throttle response. By removing the factory-restricted RPM ceiling, users will experience a significant increase in engine performance. The high-voltage output of 400–600 volts ensures a strong spark for efficient combustion.

Billet Aluminum Housing Design

The unit is enclosed in a strong orange billet aluminum casing, which functions as a cooling element for the internal transformer. This design effectively shields the sensitive electronics from vibrations and heat, promoting reliability during intense use.

Specifications

• Connector: 6-Pin (Square 2-pin + 4-pin block)
• Ignition Type: AC (Alternating Current)
• Voltage Output: 400–600V
• Manufacturer: ISO 9001 Certified

Fitment

This CDI is compatible with a variety of GY6 engines, including:

• 50cc / 80cc: 139QMA, 139QMB, 1P39QMB, 1P39QMA-2, YN139QMB, JJ1P39QMB, 139FMA-2
• 125cc / 150cc / 170cc: 157QMJ, 161QMK, 152QMI, 1P61QMK, 1P57QMJ, 1P52FMI

If your engine identifier contains "QM" or "FM" and operates on an AC CDI system, this module is likely compatible. It does not fit genuine 50cc scooters like Buddy or those with DC ignition configurations, such as the Wolf Jet II.

Not sure it fits? Contact us with your scooter's make, model and year and we'll confirm the fit before you order.

Shop more: GY6 50cc Scooter Parts (139QMB) · GY6 Scooter Parts · Scooter CDI & Ignition · Scooter Parts