You can also use a dial indicator and try to set up your sled to have as little runout as possible once clutch is mounted. This takes some time but if you find your crank runout and then counter it with your clutch runout you should be able to limit the harmful effects on your crank and main bearings. Old sled tuning dude I know was just describing this and we are about to try it on our mtn. sleds. He does this on rental machines that see extreme amounts of miles per season and swears it helps to keep them ticking a little longer. Makes sense if you think about it! First you should probably spend the coin to have your tra spinbalanced. IMHO