Just wondering why there's no cotter pin on the rear axle nut on my 09 R6s? My old Kawi had it and I think every other motorcycle I've seen had it. I'm sure it's just as safe but after a wheel came loose on my cousin's Maxima few months back and was held on by a cotter pin, I'm a little apprehensive about it haha.

they use a locking flange built into the nut.

if you are worried about it buy a safety wire pliers and roll of safety wire. drill, wire up, and done.

much safer than a cotter pin which could fall out over rough ground LOL

safety wire is the only real safe insurance. cotter pin and yamaha's system are equal in the grand scheme of things IMO .

I don't worry about it on the street correct torque and it should be good.