Motor Stuttering During Acceleration or Braking

Motor stuttering on Apollo Scooters often occurs when initiating acceleration or during braking due to mechanical looseness, synchronization issues between the motor and controller, or load-related factors. This issue affects smooth power delivery and regenerative braking performance.

Symptoms

• Jerky or stuttering motor response when starting to accelerate from a stop.
• Vibration or hesitation during regenerative braking (regen) without full hydraulic brake engagement.
• Issue may worsen under rider weight or on inclines but smooth out when unloaded.

Possible Causes

• Loose motor mounting or axle nuts allowing the motor to shift, creating uneven magnetic fields.
• Motor and controller out of sync, leading to irregular magnetic field generation during low-speed operation.
• Load sensitivity where wheel traction or resistance amplifies the stutter under real-world conditions.

Troubleshooting Steps

Elevate the scooter safely on a stable stool or chair to isolate load-related issues before ground testing.

1. Inspect motor security: Check that the motor is firmly mounted in the swingarm. Tighten axle nuts and motor screws to manufacturer torque specs using proper tools. Look for play or movement in the wheel.
2. Test under no load: With wheels elevated, accelerate and brake gently. If stuttering persists, proceed to calibration; if resolved, check tire pressure and rider-induced factors
3. Perform motor calibration: Use the Apollo App's "Motor Detection" feature to recalibrate the motor and controller sync. This resolves sync issues causing rough magnetic fields.
4. Test regen braking: Slightly press the brake lever to engage regen without hydraulic activation. Monitor for stutter; if present, verify brake sensor alignment to prevent false cutouts.
5. Check electrical connections: Inspect phase wires and hall sensor connectors for looseness or corrosion. Clean with contact cleaner and apply dielectric grease.