2004-2007 Honda Aquatrax ARX1200N3/T3/T3D Factory Service Manual, Page 115Get this manual
MAINTENANCE 4Rotate the crankshaft counterclockwise 12 of turn (180!) from the previous position and align the index line on the drive coupler boss with the index mark (arrow)Measure the No2 and No4 cylinder intake valve clearancesINDEX MARK
INDEX LINE
ADJUSTMENT
Remove the valve lifters and shims (page 10-8)Clean the valve shim contact area in the valve lifter with compressed air
VALVE LIFTER
Measure the shim thickness and record it Sixty-five different shim thicknesses are available from 1.200 mm to 2.800 mm in intervals of 0.025 mmCalculate the new shim thickness using the equation belowA(B C)A: New shim thickness B: Recorded valve clearance C: Specified valve clearance D: Old shim thickness Make sure of the correct shim thickness by measuring the shim with micrometer Reface the valve seat if carbon deposits result in calculated dimension of over 2.800 mmSHIM