1981 ATC 110 won't run

[Cade440]

I got a 1981 ATC 110 that won't run. It has spark and I the ignition timing is correct, the carb is new, the valve clearance is perfect, and the exhaust pipe is clear of obstructions. It will occasionally run for a second on carb cleaner but is extremely finicky. There is fuel getting to the carb. We also pulled it behind a truck for 20 minutes and it would occasionally start running and even slack the tow strap but it wouldn't last. The carb has been tuned to every setting imaginable, and I have successfully tuned other Honda three wheelers. Any guesses on what is going on?

[shortline10]

Check your compression . If you don’t have a compression checker , place your thumb over the spark plug hole and pull the recoil , you shouldn’t be able to hold your thumb without it leaking air , push hard btw .
Might need a topend rebuild

[Cade440]

Thanks, that was the problem. There was absolutely no compression.