Table of Contents
Advertisement
3 CYLINDER HEAD & CAMSHAFT
VALVE CLEARANCES
Camshaft, valve, valve shim and valve seat wear affects
the valve clearances. The effect of this wear is to change
the gap between the camshaft and valve shim, causing
engine noise and improper running. If the valve
clearances become too small, permanent damage to the
valve and valve seat will take place. If the valve
clearance becomes too great, the engine will become
noisy and will not run correctly.
VALVE CLEARANCE MEASUREMENT
NOTE:
•
Valve clearance measurement must be carried
out with the engine cold.
1. Remove the cam cover as previously described in
this section.
2. Remove the spark plugs to reduce compression
resistance when turning the engine.
3. Select a high gear and, using the rear wheel, turn
the engine until a pair of camshaft lobes are
positioned pointing away from the valves.
Cam Lobe Pointing Away From Valve
4. Using feeler gauges, measure and record the
clearances for this pair of valves only.
5.
Repeat the process until the valve clearances for all
valves have been checked.
NOTE:
•
If the measurement does not fall within the
specified range, adjustment must be made.
NOTE:
• The correct valve clearances are in the range
given below.
INLET
EXHAUST
CAUTION: If the valve clearances are not
A
checked and corrected wear could cause
the valves to remain partly open, which lowers
performance, burns the valves and valve seats and
may cause serious engine damage.
6. Record the measured valve clearances on a chart
similar to the example shown below.
NOTE:
•
Number 1 valve is situated on the left hand side
of the motorcycle.
Typical Valve Clearance Chart
Inlet Valve N°
1
2
3
4
5
6
Exhaust Valve N°
1
2
3
4
5
6
3.12
1AQ2"
0.10 - 0.15 mm
0.15 — 0.20 mm
Gap Measured
as measured (mm)
as measured (mm)
as measured (mm)
as measured (mm)
as measured (mm)
as measured (mm)
Gap Measured
as measured (mm)
as measured (mm)
as measured (mm)
as measured (mm)
as measured (mm)
as measured (mm)
Hide quick links:
Advertisement
Table of Contents
