yup, all 4 corners....
next thing to check is the other 2 cylinders.
after you check those for damage, I would investigate the thermostat. If you let the sled "warm up" before riding it and this happened way down the trail, then usually it would tend to be the thermostat is stuck open it will never come up to temp properly and expand the cylinders. The first time you lean on the gas good and hard the piston gets hot,expands faster then the cylinder expanded for the proper side clearance.
Seen a bunch of them that the thermostat center comes off the pin in the center, holding it open, which keeps the engine ice cold for a long time.
next thing to check is the other 2 cylinders.
after you check those for damage, I would investigate the thermostat. If you let the sled "warm up" before riding it and this happened way down the trail, then usually it would tend to be the thermostat is stuck open it will never come up to temp properly and expand the cylinders. The first time you lean on the gas good and hard the piston gets hot,expands faster then the cylinder expanded for the proper side clearance.
Seen a bunch of them that the thermostat center comes off the pin in the center, holding it open, which keeps the engine ice cold for a long time.