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:

Throttle Control System Inspection
Check the throttle grip free play [A]. If the free play is incorrect, adjust the throttle cables. Throttle Grip Free Play Standard: 2 3 mm (0.08 0.12 in.) Check that the throttle grip [B] moves smoothly from full open to close, and the throttle closes quickly and completely by the ...

Water Pump Inspection
Remove the left lower fairing (see Lower Fairing Removal in the Frame chapter). Check the drainage outlet passage [A] at the bottom of the water pump body for coolant leaks. If the mechanical seal is damaged, the coolant leaks through the seal and drains through the passage. Replace th ...

Hoses and Pipes
Hose Installation Install the hoses and pipes, being careful to follow bending direction. Avoid sharp bending, kinking, flattening or twisting. Run the hoses (see Cable, Wire, and Hose Routing section in the Appendix chapter). Install the clamp [A] as near as possible to the hose end ...