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:

Master Cylinder Inspection (Visual Inspection)
Remove the master cylinders (see Front/Rear Master Cylinder Removal). Disassemble the front and rear master cylinders (see Master Cylinder Rubber Parts Replacement in the Periodic Maintenance chapter). Check that there are no scratches, rust or pitting on the inner wall [A] of each ma ...

Daily Checks
Check the following items each day before you ride. The time required is minimal, and habitual performance of these checks will help ensure you a safe, reliable ride. If any irregularities are found during these checks, refer to the Maintenance and Adjustment chapter or see your dealer fo ...

Rider’s Seat Installation
Insert the tabs on the front of the rider’s seat into the slots in the frame and secure the seat with mounting bolts. Install the seat cover and bolts. A. Rider’s Seat B. Tabs C. Slots D. Stays ...