the range on my g4 is way lower than advertised, like maybe 8 miles on a full charge.

Diagnosis

The Gotrax G4 is marketed with a theoretical range that assumes "ideal conditions": a 150lb rider on flat pavement at a constant low speed. When you see a drop to 8 miles, you are experiencing a massive increase in rolling resistance and electrical inefficiency. The most common culprit is "tire squish," where low PSI increases the contact patch between the rubber and the road, forcing the motor to draw significantly more current from the battery to maintain speed. Furthermore, the G4 uses a specific battery chemistry that is sensitive to temperature and discharge depth. If you are riding in "Sport" mode or frequently accelerating from a complete stop, the peak current draw creates heat in the cells, which wastes energy that should be going toward distance. You can confirm this by checking your tire firmness; if you can indent the tire by more than 1/4 inch with your thumb, your range will be slashed by 30-50% regardless of battery health.

How to Fix It

To recover your lost range, you must optimize the mechanical efficiency of the scooter and the power delivery settings. Follow these exact steps:

1. Locate the PSI rating on the sidewall of your G4 tires. You are aiming for 45-50 PSI. Do not guess; use a digital pressure gauge.
2. Inflate both tires to 50 PSI. This minimizes the rolling resistance and reduces the load on the 350W motor.
3. Switch your ride mode to "Eco" or "Standard" via the LED display. Avoid "Sport" mode unless climbing a steep incline, as the aggressive torque curve drains the battery exponentially faster.
4. Adjust your riding technique: instead of flooring the throttle from a dead stop, give the scooter a manual "kick-start" push for the first 2-3 feet before engaging the motor. This prevents the high-amp spike that occurs during initial acceleration.
5. Check your brake levers. Ensure the brake handles are not resting too close to the grip, which can cause the electronic braking system to engage slightly, creating a constant drag on the motor.

If That Didn't Work

• Calibrate the Battery Management System (BMS): Sometimes the range indicator drifts. Perform a "deep cycle" by riding the scooter until it shuts off completely, then charge it to 100% without interruption for 6-8 hours. This resets the voltage thresholds and can sometimes recover "ghost" capacity.
• Inspect for Mechanical Drag: Lift the scooter and spin the wheels by hand. If the wheel stops quickly or makes a rubbing sound, your brake calipers may be misaligned or the disc rotor may be warped. Use a 5mm Allen key to loosen the caliper bolts, center the rotor, and retighten to ensure the wheel spins freely.
• Check for Battery Cell Degradation: If the scooter shuts down abruptly at 20% or 30% remaining, you likely have a "dead cell" within the pack. This cannot be fixed via software; you will need to replace the battery pack entirely. Look for a replacement pack that matches the 36V specifications of the G4.
• Verify Charger Output: Use a multimeter to ensure your charger is delivering the correct voltage to the battery. If the charger is failing, it may report a "full" green light while the battery is only at 60-70% capacity.

Heads Up

• Never store your G4 with a completely dead battery; this can lead to "deep discharge" where the BMS locks the battery permanently for safety, rendering it unchargeable.
• Avoid riding in temperatures below 40°F (4°C). Lithium-ion batteries have higher internal resistance in the cold, which can temporarily drop your range by as much as 40%.
• Check your tire pressure every 14 days. The G4 tires are prone to slow leaks, and a drop of even 5 PSI can noticeably impact your mileage.
• Avoid using the "Sport" mode for the entire trip. Use it only for bursts of speed, then drop back to "Standard" to preserve the battery's voltage curve.