Valve Seat Repair; Cylinder Inspection - Suzuki 2005 GSF1200 Service Manual

1D-38 Engine Mechanical:

Valve Seat Repair

The valve seats (1) for both the intake and exhaust
valves are machined to two different angles. The seat
contact surface is cut at 45°.
Intake
Seat angle 15°/45°
0.9 – 1.1 mm
Seat width
(0.035 – 0.043 in)
Valve 30 mm
diameter (1.18 in)
Valve guide 5.000 – 5.012 mm
I.D. (0.1969 – 0.1973 in)
CAUTION
!
• The valve seat contact area must be
inspected after each nut.
• Do not use lapping compound after the
final cut is made. The finished valve seat
should have a velvety smooth finish but
not a highly polished or shiny finish. This
will provide a soft surface for the final
seating of the valve which will occur
during the first few seconds of engine
operation.
NOTE
After servicing the valve seats, be sure to
check the valve clearance after the cylinder
head has been reinstalled. Refer to "Valve
Clearance Inspection and Adjustment: in
Section 0B".

Cylinder Inspection

Refer to "Engine Top Side Disassembly: ".
Refer to "Engine Top Side Assembly: ".
Cylinder Distortion
Check the gasket surface of the cylinder for distortion.
Use a straightedge and thickness gauge. Take clearance
readings at several places. If any reading exceeds the
service limit, replace the cylinder.
B649G11406069
1
I649G1140361-01
Exhaust
15°/45°
0.9 – 1.1 mm
(0.035 – 0.043 in)
27 mm
(1.06 in)
5.000 – 5.012 mm
(0.1969 – 0.1973 in)
B649G11406058
Special tool
: 09900–20803 (Thickness gauge)
Cylinder distortion
Service limit: 0.2 mm (0.008 in)
Cylinder Bore
Measure the cylinder bore diameter at six places. If any
one of the measurements exceed the limit, overhaul the
cylinder and replace the piston with an oversize piston.
The remaining cylinders must also be rebored
accordingly; otherwise, the imbalance might cause
excessive vibration.
Special tool
(A): 09900–20508 (Cylinder gauge set)
Cylinder bore
Standard: 79.000 – 79.015 mm (3.1102 – 3.1108 in)
Service limit: 79.080 mm (3.1134 in)
(A)
Piston-to-cylinder Clearance
Refer to "Piston and Piston Ring Inspection: ".
I649G1140258-01
I649G1140259-02
I649G1140260-01