Why does my polaris snowmobile only run on one cylinder?

[Polaris it up!]

i have a 2000 xc sp 700. ran fine for a long time but one day it ran like crap. only on one cylinder and topped out at like 60. i out in new plugs and checked for spark. they both had good spark but one of the plugs was silverish at the tip, not black like the other. the sled still ran on one cylinder and was not wet at all. what going on with it? anyone know why it would run like this randomly?

[el.tuco]

you need to pedal it faster

[el.tuco]

you need to pedal it faster

[Jeff B]

Check compression to see if you didnt burn a hole through the piston. If you had an intake or head gasket leak its easy to do.