That is the Swing arm bolt, i have no idea why yamaha made it go threw the motor. :? Every blaster i have had was apart when i got it so never had to fight with one. But i would say, Jack up the frame to get wieght off the swingarm, and spray some WD40 in there and put a wrench on the other end to make it turn freely then just tap it out with a
, and if it wont come out ever after you get it in the swinger some use a punch on it. Hope this helps you out..
06 TRX450r , 85 ATC250r, 01 TRX300ex, 84 ATC110
88 Mustang GT