2000 Yamaha YFM400FWA(M) Factory Service workshop Manual, Page 309Get this manual
REAR SHOCK ABSORBER AND SWINGARM SWINGARM REMOVAL 1.Inspect: Swingarm free play
Inspection steps: Check the tightening torque of the nuts (swingarm)Nut (swingarm): 59 Nm (5.9 kg, 43 ft lb)