If it's just started, I'd look for an air leak. Otherwise, try going up one size on the pilot jet.

A small amount of "popping" is to be expected when decelerating with the throttle closed though, as you are running a much leaner mixture than the engine would expect to see at that speed. What's happening is you don't have a rich enough mixture to ignite reliably when the throttle is closed, so the unburned mixture accumulates in the pipes. Every so often the "waste" spark (Evos fire on both compression and exhaust stroke) will touch off the mix in the pipes, causing the "pop". Such is life in the land of the carburetor.

 

Ha ha , you funny.

 

finally got it sorted...I lifted the needle in the carb.. now all good.