KYMCO Mongoose 50-2T, Service Manual

Page: 122 / 258

7
. CYLINDER HEAD/VALVES
(90cc/70cc/50cc-4T)
7-12
VALVE SPRING INSPECTION
Measure the free length of the inner and
outer valve springs.
Service Limit :
90cc:
Inner: 30.8 mm (1.232 in)
Outer: 33.5 mm (1.34 in)
70cc:
Inner: 28.4 mm (1.136 in)
Outer: 32 mm (1.28 in)
50cc-4T: 34 mm (1.36 in)
Measure compressed force (valve spring)
and installed length.
Replace if out of specification.
Service limits :
90cc:
IN : 3.47
～
4.27 kg at 26 mm (1.04 in)
EX : 8.29
～
10.19 kg at 29 mm (1.16 in)
70cc:
IN : 4.3 kg at 22.45 mm (0.898 in)
EX : 8.4 kg at 25.25 mm (1.01 in)
50cc-4T:
19.2
～
22 kg at 19.65 mm (0.786 in)
Check the intake manifold and O-rings for
wear or damage.
O-ring