How to Change the Coolant in a 2021 GAS GAS MC-E 5
The 2021 GAS GAS MC-E 5 is an electric dirt bike, and unlike most gas-powered models, it uses an electric motor instead of a combustion engine with a standard coolant system. However, some electric models do have liquid-cooling to keep the motor and control electronics at safe operating temperatures. The MC-E 5 features a sealed, low-maintenance cooling system with unique service requirements. Below are proprietary instructions for MotoSport.com customers for changing the coolant in your 2021 GAS GAS MC-E 5.
Key MC-E 5 Notes
- The MC-E 5 uses a liquid cooling system designed for its electric motor and control system–do not use standard engine coolant change techniques blindly.
- Never open the cooling system when the bike is recently operated or the cooling circuit is warm–allow the bike to fully cool for at least 30 minutes before beginning service for your safety*.
- Use only the manufacturer-recommended ready-to-use coolant for electric motorcycles. Always check your owner's manual first.
- Coolant change interval: Inspect at least once a year, and replace immediately if coolant appears cloudy, dirty, or has dropped below minimum levels.
- Capacity: Approx. 0.7 liters (0.7 qt.) is required for a full system fill on most models.
Required Tools & Supplies
- Replacement coolant compatible with electric motorcycles
- 10mm socket or wrench
- Drain pan
- Funnel
- Shop towels
- Protective gloves & eyewear
Step-by-Step Coolant Change Process
- Preparation:
- Ensure the MC-E 5 is completely powered off and cool to the touch.
- Place the bike upright on a stable surface.
- Wipe any dirt or debris away from the radiator cap and water pump area.
- Draining Old Coolant:
- Locate the water pump at the lower right side of the motor assembly.
- Position a drain pan under the water pump.
- Remove the drain screw (typically M6) and allow all old coolant to drain out.
- Remove the radiator cap to facilitate draining.
- Inspect the removed liquid for contamination or particles–this may indicate the need for a system flush (not routine for electric models unless contamination is seen).
- Seal and Close:
- Replace the drain screw with a new seal ring if available.
- Tighten the screw to 6 Nm (4.4 lbf ft).
- Refilling with New Coolant:
- Insert a funnel into the radiator fill neck.
- Slowly pour in fresh coolant until the level is 10 mm (0.39 in) above the radiator fins.
- Wait a few moments for air bubbles to escape and double-check the fill level, topping up if needed.
- Burping the System:
- Gently rock the bike side-to-side or tap the radiator hoses to help trapped air escape.
- Look for air bubbles rising in the fill neck; refill if the level drops.
- Final Checks:
- Reinstall the radiator cap securely.
- Double-check all fasteners for proper tightness and wipe away any spills.
- If the radiator cap or hoses show cracks or leaks, replace them immediately using OEM parts.
- Dispose of Old Coolant Properly:
- Used coolant is hazardous–seal it in a container and bring it to an approved recycling or hazardous waste facility.
Model-Specific Details
- Unlike combustion-engine dirt bikes, the MC-E 5 has no cylinder head or traditional engine block. The cooling system mostly protects sensitive electronic components from overheating.
- Never use coolant additives meant for metal corrosion or anti-boil in this system unless specifically labeled as safe for electric motorcycles.
- Check the MC-E 5's radiator shrouds and hoses periodically for signs of external damage; coolant leaks in an EV must be addressed immediately to prevent expensive motor or controller repairs.
Routine coolant maintenance is key for electric performance and reliability. For all parts and fluids, shop MotoSport–your one-stop source for everything MC-E 5.
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Disclaimer: This guide is provided for general informational purposes only and is not intended to replace your motorcycle's official owner's manual. Always refer to your manufacturer's documentation for model-specific instructions, torque specifications, safety procedures, and maintenance requirements. If you are unsure or inexperienced, consider seeking assistance from a qualified mechanic or technician.