2000 Yamaha YFM400FWA(M) Factory Service workshop Manual, Page 254Get this manual
REAR AXLEFINAL DRIVE GEAR AND DRIVE SHAFT
5) Therefore, shim thickness "B" is 0.63"B"= 45.531.05 (34.9511.00)46.58 45.950.63 6) Round off the hundredth digit and select the appropriate shim(s)In the example above, the calculated number is 0.63The chart instructs you to round off to at the hundredth placeThus, the shim thickness is 0.65 mmHundredths 0, 1, 3, 4, 5, 6, 8, Rounded value 10
Shims are supplied in the following thicknessesRing gear shim Thickness (mm) 0.25 0.40 0.30 0.45 0.35 0.50