went riding last night 2 feet of fresh snow sled was bogging quite abit on the powder but then if you got on a hardpack it would clear up.. started to bog pretty bad i though i just fowled the plugs went to put new plugs in today and the clutch side sparkplug wasmetalic grey andbeat up a bit the hole has not very much compression. other side has lots of compression and spark plug looks good.... anyone had this happen to them?? i havnt pulled the jug off to take a look yet. i hope i just neeed new piston and rings