Hi, I'm new to this forum and have a question about a recent problem with my 500 Xplorer. During the last time I was plowing snow (I have a Swisher 50" Plow), I could not get the motor to higher rpms. It would start missing, bogging down, and backfiring. I originally thought that it might be frozen water restricting the fuel flow. i left it in my neighbor's heated barn overnight- That wasn't it. Air filter looks good, Spark Plug Looks good. All Fluids are at recommended levels. It starts and runs fine until you try to run over 3000 rpms (I am estimating as there is not Tachometer). Anybody have any thoughts???