2008 Suzuki LT-A400/F, LT-F400/F ATV Service Manual, Page 104Get this manual
1D-28 Engine Mechanical:
Valve Seat Repair
The valve seats (1) for both the intake and exhaust valves are machined to three different anglesThe seat contact surface is cut at 45 45 15
B827H21406014
Camshaft Inspection
The camshaft should be checked for wear and also for runout of cams and journals if the engine has been noted to produce abnormal noise if the engine has been noted to produce abnormal noise or vibration or to lack output powerAny of these malconditions could be caused by worn camshaft
B827H21406015
I827H1140074-01
Intake 15 45 0.9 1.1 mm Seat width (0.035 0.043 in) Valve 30.6 mm diameter (1.20 in) Valve guide 5.000 5.012 mm I.D(0.1969 0.1973 in) Seat angle!