Suzuki DF 2.5 Service Manual page 79

VALVE/VALVE GUIDE
Using the micrometer and a small bore gauge, take the diameter
readings on the valve stems and the guides in order to check the
guide to stem clearance. Be sure to take readings at more than
one place along length of each stem and guide.
 09900-20205: Micrometer
Valve stem outside diameter
Measure the valve stem outside diameter using the micrometer.
Valve stem outside diameter:
Standard:
IN. 3.975 – 3.990 mm (0.1565 – 0.1571 in)
EX. 3.960 – 3.975 mm (0.1559 – 0.1565 in)
Valve guide inside diameter
Measure the valve guide inside diameter using a small bore
gauge.
Valve guide inside diameter:
Standard:
IN. & EX. 4.000 – 4.012 mm (0.1575 – 0.1580 in)
Valve guide to valve stem clearance:
Standard:
IN. 0.010 – 0.037 mm (0.0004 – 0.0015 in)
EX. 0.025 – 0.052 mm (0.0010 – 0.0020 in)
Service limit: IN. 0.075 mm (0.0030 in)
EX. 0.090 mm (0.0035 in)
If the measurement exceeds the service limit, replace the valve
and/or the cylinder head.
Valve stem deflection
If unable to measure the valve guide inside diameter, measure
the "Valve stem deflection".
 09900-20602: Dial gauge
09900-20701: Magnetic stand
1. Install the valves into the valve guide.
2. Lift the valves 8 – 10 mm off seat.
3. Move the valve head in the direction "X – Y" and measure
the deflection.
Valve stem deflection:
Service limit: IN. & EX. 0.35 mm (0.014 in)
If the measurement exceeds the service limit, replace the valve
and/or the cylinder head.
POWER UNIT 6-13