to start the story, my buddy, 660_rider03 put his 660 raptor engine in the shop about 2 months ago, to have it serviced, a new timing chain put in and some valve work done.
well he finally got the engine back two days ago, and put it in yesterday. he called me to help him, but i was busy so he started by himself. i got done with my work and headed over to help him out. i was late and he already had the motor in place and mounted. we hooked up the battery, and the pipe and he started it up. it idled nicely for about 2 minutes, then started making a wierd clanking/rattling noise, and then shut off. he tried to start it again and the starter wouldnt turn over the engine, it sounded like it was catching on something. well a few more pops of the starter, and it fired right back up. it idled for another minute or so and then came the rattling again. i said "man did you put enough oil in it?" "yea man, its fine. i checked it when it shut off and its all good." the rattling got worse and all of a sudden BOOM!POP!CLANK. the whole side of the valve cover blew off and 2 small screws shot out at light speed, and hit me on either side of the boys. i fell to the ground screaming bloody murder, and saying something about suing the Yamaha Corporation for the loss of my penis.
but thats not the point, the screws came form inside the engine, they shot out from the inside of the top of the valve cover. ill try to get a pic, but do any of you 4 stroke guys have any idea what the bolts came from? they are esactly the same size as the ones that hold the rear plastics on the frame of the shee.