400ex shuts off when it gets hot What is wrong with it?

If a 400EX ATV shuts off when it gets hot, it could indicate an overheating issue, possibly due to low coolant levels, a faulty thermostat, or a blocked radiator. Additionally, it might be related to an electrical issue, such as a failing ignition coil or a weak battery that can't handle the heat. Inspecting these components can help identify the exact cause. Regular maintenance and cooling system checks are essential to prevent overheating problems.