Below is a quote from a response to similar question from yesterday:
"Easiest thing to check is trash in the main jet. if it idles fine, then the idle circuit and low speed jet is clear. if it bogs off idle that's when it's transitioning to the main jet."
I will go ahead and open up the carb and check the main jet, but please respond to this post as if the main jet is squeaky clean.
Below is my post:
Only starts and runs on Full chock.
Does not matter what position I have my "mixture" screw. Tried it at zero, 1 turn, 2 turn, up to five turns. Spent a few hours confirming that the position of the mixture screw does not resolve issue.
Runs great at idle and if I slowly engage throttle, it will rev up as expected. But, quick rev up or when I am trying to drive it, it spits and sputters and looses power.
I also use a propane bottle and did not find any obvious leaks, and the vacuum port is hooked to fuel peacock and I also made sure to simply block the port with my finger to see if that would resolve the issue.
New Carb (after market), New Coil, Fresh Gas. No leaks at manifold boot, hot battery. Good gas flow. Runs too good to be a valve issue, or cylinder, great compression.
I can move the choke out a tiny bit, and it will still run, but will still bog down when I try to power it up.
I also have a 250 trail boss Polaris that I require to run at full choke, but it has power at all throttle potions.
I suspect it is running rich as the choke is on, but will not run with it off.
Any details would be appreciated.