I am working on a 1987 LT230EH.

It is very cold blooded, must be warmed up for 15 minutes to run somewhat properly.

Here is what I've done to no avail:

Ohmed out all coils, stator, and pickup... All test within spec.
Rebuilt carb with K&L kit, cleaned. Carb bowl was dirty, jets vere not clogged.
Replaced air filter.
Adjusted valves to .002" intake and .005 exhaust.
Replaced spark plug and cap.
Compression tests 150-170 hot and cold.
Has decent spark, not great.
Oil Change.
Replaced gas and installed fuel filter.


The quad runs poorly and stalls a lot, smokes a little bit.
You can rev the engine up pushing the throttle slowly, if you stab it the quad dies.

What am I missing here, please help. I am en experienced mechanic and have tested everything I can think of, to no avail.

 

Its not getting enough gas. Either because your carb is jetted wrong or because your airfilter is not restrictive enough or a hole in the filter or behind carb in tubing. Or maybe you have the lid off the airbox.

Either make the filter more restrictive or jet the carb right for the increased cfm.