I got a 2000 mxz 700 with this problem.Start the sled an it idles fine for awhile the just shuts off.Pull the rope right away an it runs for awhile again then dies.When you ride the sled if you go over 7000 rpm is acts like you hit the kill switch then right before it completely shuts off it will come back to life.But everytime it dies you can restart it right away an it will run for awhile again.Ive done just about everything I can think of to eliminate whats going on with this sled.Id rather try to fix it on my own than bring the sled to a mechanic an let them just throw parts at it till the problem goes away.