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:

Chain Slack Inspection
Set the motorcycle up on its side stand. Rotate the rear wheel to find the position where the chain is tightest, and measure the maximum chain slack by pulling up and pushing down the chain midway between the engine sprocket and rear wheel sprocket. A. Chain Slack If the ...

KIBS Hydraulic Unit Inspection
Remove the KIBS hydraulic unit (see KIBS Hydraulic Unit Removal). Visually inspect the connector terminals [A]. Replace the KIBS hydraulic unit or main harness if either of the terminals are cracked, bent, or otherwise damaged. If the KIBS hydraulic unit connector is clogged with mud or ...

Sidestand Switch Operation Inspection
Raise the rear wheel off the ground with the stand (see Rear Wheel Removal in the Wheels/Tires chapter). Inspect the sidestand switch [A] operation accordance to below table. Sidestand Switch Operation If the sidestand switch operation does not work, inspect or replace the foll ...