Kawasaki Ninja Service Manual: Valve Seat Inspection

Kawasaki Ninja Service Manual / Engine Top End / Valves / Valve Seat Inspection

Measure the outside diameter [D] of the seating pattern on the valve seat.

If the outside diameter is too large or too small, repair the seat (see Valve Seat Repair).

Valve Seating Surface Outside Diameter Standard:

Exhaust 23.9 24.1 mm (0.941
0.949 in.)


Intake 30.4 30.6 mm (1.197
1.205 in.)


Valve Seat Inspection


Measure the seat width [E] of the portion where there is no build-up carbon (white portion) of the valve seat with a vernier caliper.

Good [F]

If the width is too wide [G], too narrow [H] or uneven [J], repair the seat (see Valve Seat Repair).

Valve Seating Surface Width Standard:

Exhaust 0.8 1.2 mm (0.03
0.05 in.)


Intake 0.5 1.0 mm (0.02
0.04 in.)


Valve-to-Guide Clearance Measurement (Wobble Method)
If a small bore gauge is not available, inspect the valve guide wear by measuring the valve to valve guide clearance with the wobble method as indicated below. Insert a new valve [A] into the gu ...

Valve Seat Repair
Repair the valve seat with the valve seat cutters [A]. Special Tools - Valve Seat Cutter Holder Bar [B]: 57001 -1128 Valve Seat Cutter Holder, 4.5 [C]: 57001 -1330 [For Exhaust Valve Seat] V ...

Other materials:

Engine Sprocket Installation
Replace the sprocket washer and axle cotter pin. Install the engine sprocket onto the output shaft. Apply molybdenum disulfide oil solution to the threads and seating surface of the engine sprocket nut. Tighten: Torque - Engine Sprocket Nut: 145 N·m (14.8 kgf·m, 107 ft·lb) NOTE ...

Stator Coil Installation
Apply a non-permanent locking agent to the threads of the stator coil bolts and tighten them. Torque - Stator Coil Bolts: 12 N·m (1.2 kgf·m, 106 in·lb) Using a high flash-point solvent, clean off any oil or dirt that may be on the silicone sealant coating area. Dry them with a clea ...

Clutch Installation
Apply engine oil to the needle bearing [A] and the sleeve [B]. Install: Needle Bearing Sleeve Install the clutch housing [A]. Fit the holes [B] and projections [C]. Engage the clutch housing gear and the crankshaft primary gear. Install the spacer [A] and the clutch ...