Dear Mr. Know-It-All,
My 2022 Beta Evo 250 trials bike is experiencing issues with the fan. When I ride for about 30 minutes, the fan starts surging and pulsing before returning to normal. I have checked that the fan is spinning freely and nothing is disconnected. What could be causing this problem?
Ron Rollins
Although I haven’t personally faced such an issue, I consulted with my knowledgeable friends to help you find a solution. Check the rear fender near the airbox, where both the fan and thermal sensor plug into the main harness of the bike. Look for any loose connections or debris like dirt or corrosion. If those areas are fine, focus on the thermal sensor located at the bottom-right corner of the radiator. This sensor determines when the fan should run and at what temperature it should turn on. If the sensor is malfunctioning, it may cause the fan to operate erratically and inconsistently.
If you don’t mind sharing your failures with the world, feel free to send evidence to [email protected] or Mr. Know-It-All, Dirt Bike P.O. Box 957, Valencia, CA 91380-9057.