Joyner JNSZ1100SV Owner's Manual page 61

3.2. Valve spring
3.2.1. Use a square ruler to measure the
right angle of the valve spring.
Replace the spring if it fails to meet
the specifications.
[Limit] 1.2mm
3.2.2. Measure the free state of spring
[Benchmark value] 37mm
3.3. Routine checks on throttles
3.3.1. Check to see if there are some
deformations, obvious tears and
wears
Check list on valve Unit: mm
item
wide
Width of valve top
3.3.2. Checks on the clearance between
the throttle guiding pipe and throttle
thrusting rod
3.3.2.1. Use a dial gauge to measure the
inner diameter of the
throttle-guiding pipe, and use a
caliper to measure the outer
diameter.
3.3.2.2. Work out the differences of the
measured values. If it is above the
specified limits, the throttle or the
guiding pipe must be replaced.
Attention The measurement points are
shown as the figure. Work out the
clearance of the final torn and worn section
item
Valve guide
Inside diameter(mm)
Valve stem
diameter (mm)
IN
Spacing
(mm)
EX
standard
IN 0.85～1.41
EX 1.07～1.36
IN 1.0±0.2
EX 1.0±0.2
standard
φ5.0
outside
φ5.0
0.056
0.020mm
0.066
0.030mm
limit
—
—
0.75
0.75
limit
—
—
～
0.07
～
0.08