Suzuki GSX-R750 Service Manual page 88

3-40 ENGINE
VALVE STEM END CONDITION
• Check the valve stem end face for pitting and wear.
VALVE SPRING
The force of the coil springs keeps the valve seat tight. Weak-
ened springs result in reduced engine power output, and often
account for the chattering noise coming from the valve mecha-
nism.
• Check the valve springs for proper strength by measuring their
free length and also by the force required to compress them.
• If the spring length is less than the service limit, or if the force
required to compress the spring does not fall within the range
specified, replace both the inner and outer springs as a set.
[ 09900-20102: Vernier calipers
Valve spring free length (IN & EX):
Service limit: 37.8 mm (1.49 in)
Valve spring tension:
Standard: (IN & EX): 19 kgf/32.85 mm (41.9 lbs/1.29 in)
19 kgf
32.85 mm