Bogging

If the bogging is associated with overheating then it is likely due to a cerebration problem. However, It could be other than the needle setting. Check the fuel line; Check the filter; check the tank lid? Check for air leaks at the engine mounting hole. If you throw it out on the track and initially there is no bogging and then slowly if starts to overheat and then starts to bog. Then it is most likely the carburetor. However, other problems will give you the bogging symptom.

If the motor bogs from the “get-go”; even before it heated-up, Then remove the clutch bell and check the clutch. Are the springs OK? Are the spring(s) broken? Are the shoe(s) dragging on the Clutch bell? Are the shoes in backwards (leading instead of trailing)?

Too much brake drag?
Binding in the driveline?
Wheels scraping on the rear camber link?
Gear mesh too tight?
Geared too Tall?

These little glow engines don’t start to develop horsepower until they wind-up into the their upper end of the RPM range. Any drag or hang-up down low will give you the Bog.