Ask him to open the idle screw (CCW) and see if the engine speeds up.
If it does, then it is lean. Adjust the ATV to get the engine back to a good idle, then open the idle screw again.
Keep doing this until the engine stops speeding up.
From this, adjust the idle so that you get good transistion and solid idle.
Once this is done, then adjust the high speed screw to get good WOT power and uplines.
ORIGINAL: Hogpilot
Here's the Problem; The engine Runs smooth and Flawlessly from 1/4 stick UP.
From Idle up to 1/4 throttle the engine hesitates when throttle is added, He described it like; below 1/4 throttle the engine sounds like a rich 2 stroke, but throttles like a lean engine. The idle is also rough.
There is no excess oil on the bottom of the plane.
He thinks he needs to tweak the low end, but not sure which way to go.
I hope I gave enough info for Ya'll to diagnose the problem.
Any Help or Advice will be appreciated.
Thanks,
David