Tag Archives: KnowItAll My

HOT RUNNING TRIALS BIKE: MR. KNOW-IT-ALL

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

via [email protected]

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.

For more advice from Mr. Know-It-All, click here.

TPI CRANKCASE PRESSURE SENSOR ISSUES: MR KNOW IT ALL

Dear Mr. Know-It-All,

My 2023 KTM 300XC-W has about 120 hours on it and has been flawless … until yesterday. The bike was running as if it was fouling a plug. It would not clean out, like a bad case of laryngitis. I changed the plug, put fresh fuel in it and made sure my filter was spotless, and still no changes. What could be the culprit?

Alex B

via [email protected]

Alex, it’s a new-world order with these fuel-injected machines. The TPI KTMs have numerous sensors, and one of these is most likely your machine’s infection. I believe it’s the crankcase pressure sensor (has a black tube leading to the back of your cylinder), and over time the tube accumulates debris and carbon from within the cylinder. Once clogged, it provides a false reading to the machine’s brain, the ECU. I would remove this tube and the sensor itself, and clean it with a contact cleaner and compressed air. Once scoured, your machine should run crisp and clean. This process should be a periodic form of maintenance on the TPI machines.

CRAMPED
Dear Mr. Know-It-All,

I’m a Beta 500 dualsport rider and have trouble getting forward in the turns. I’m pretty flexible, but it feels like the bars are in my stomach, and my rear end is hanging off the rear fender. I’m 6-foot-4, 205 pounds in full dress.

Thanks for the feedback (if you actually answer this!)

Drew L.

If you don’t mind displaying your ignorance for the world to see, who are we to deny the opportunity? Send evidence of your failures to [email protected] or Mr. Know-It-All

Dirt Bike P.O. Box 957

Valencia, CA 91380-9057