My name is John, I'm new to this forum and have a technical question for a seasoned tuner. This is related to a FE290 4-stroke Kawasaki engine fitted with a Mikuni VM22 round slide carb (Large Frame). I'm struggling trying to tune this engine to accelerate from idle to the mid range throttle position without falling on its face. This carb has the primary type needle jet, and I've heard that a 4-stroke doesn't develop enough velocity through the venturi from idle to mid range to pick fuel from a primary type needle jet, and that a bleed type system would be the better choice. Now I can install a much larger pilot jet and it will pick up and take off, but it not like it should. The adverse effect of the larger pilot jet is that it richins it up to much at idle. The top end rpm is awesome with this carb, I just need to get the bottom end rpm to pick up a little quicker. Any tips or idea's out there or any confirmations about the Bleed type needle jet system?