Yamaha TT-R125(M) Owner's Service Manual page 238

VALVES AND VALVE SPRINGS
2. Measure:
b Installed length
3. Measure:
ASSEMBLY AND INSTALLATION
Valve
1. Apply:
2. Install:
NOTE:
Make sure that each valve is installed in its
original place.
Install the valve springs with the larger pitch
a facing upwards.
b Smaller pitch
4 - 30
Compressed spring force a
Out of specification
Compressed spring force:
Intake:
14.0 ~ 16.1 kg at 25.6 mm
(30.86 ~ 35.49 lb at 1.01 in)
Exhaust:
14.0 ~ 16.1 kg at 25.6 mm
(30.86 ~ 35.49 lb at 1.01 in)
Spring tilt a
Out of specification
Spring tilt limit:
Intake:
2.5˚/1.4 mm (0.06 in)
Exhaust:
2.5˚/1.4 mm (0.06 in)
Engine oil
(onto the valve stem and valve stem
seal)
Valve spring seats 1
Valve stem seals 2
Valves 3
Valve springs 4
Valve spring retainers 5
ENG
Replace.
Replace.
New