I have a 2002 honda foreman rubicon 500 that will idle sometimes without the choke on,but I usually have to leave it on. It will spit and sputter and blow white smoke as if it was running lean but when I check the plug it’s always black. I have rebuilt and clean my carb more times then I can count and I have also replaced my air filter and spark plug and but still no change.it had sit out in the weather at my grandparents house for about a year before I rescued it. Any advice would be greatly appreciated!!