Need Help With A Suzuki 4 Wheel Drive

[350 oddyman]

I HAVE A 91 SUZUKI LT 250 4 WHEEL DRIVE IT STARTS AND RUNS PERFECT BUT WHEN YOU PUT IT IN GEAR AND TAKE OFF SLOWLY IT DOES ALRIGHT BUT WHEN YOU MASH THE THUMB THROTTLE DOWN ALL THE WAY IT WILL START MISSING. THE PLUG WHEN REMOVED HAS A DRY BLACK FLUFFY COATING ALL OVER IT I PUT A NEW PLUG IN AND AFTER A FEW SHORT MINUTES OF RIDING I REMOVED THE PLUG AND IT HAD A DRY BLACK FLUFFY COATING ALSO! I HAD THE CARBURATOR REBUILT BY A SUZUKI DEALER THIS DID NOT HELP AT ALL DOES ANYONE HAVE A IDEA WHAT COULD BE WRONG???I HATE TO PUT IT IN A SHOP BECAUSE IT IS EXPENSIVE

[phatswinn]

sounds like ur running very rich, clean the filter and try to run it with out the airbox on and see if its better, if it is go down a main jet size

[Live2Ride300]

Is it all stock? Have you done any mods to it? Is the engine stock?

[350 oddyman]

IT IS ALL STOCK NO MODS AND IT HAS A BRAND NEW AIR FILTER ON IT SO I DONT THINK ITS THAT I WILL TRY RUNNING IT WITHOUT THE AIRBOX TO SEE IF THAT SOLVES IT THEN I WILL REJET