Heyy guys inhave yamaha warrior 350 2001 my woodruff key snaps its the second one i put in and snapes on me rightaway i really dont know why. At first the magneto coul went on me 2 years ago anf never had time to work on it so i finally got that done it started up first shot i was happy i was like yes im gonna go ride today tryed to start it again realized the flywherl was just spinning not ingauging so i took it apart relized the woodruff key broke so i took the one out my other 350 motor intalled it and the same thing started up first shot right away 2 /3 times then the same thing happend Realized the flywheel was just spinnjgn again not engauge too it apartt and it was broken again plz someone let me know some tricks or soemthing thanks

 

First, check you have got the right "magneto coil" and have fitted it correctly as, if the flywheel hits it, something has to give. If everything is OK, you must not have tightened the holding bolt properly first time. The correct torque is critical on these, too loose and it shears the key, too tight and you won't get it off again. Now it has sheared, it will have scored the tapers on crank and flywheel. I grind them in like a valve seat if this happens. When the tapers are both a uniform mat grey once the grinding paste is washed off, make sure both tapers are clean and grease/oil/paste free, fit a new key and torque it up to the correct torque.