Suzuki VZR1800 2007 Service Manual page 95

3-38 ENGINE
• Clean and assemble the head and valve components. Fill the
intake and exhaust ports with gasoline to check for leaks.
• If any leaks occur, inspect the valve seat and face for burrs or
other things that could prevent the valve from sealing.
'
Always use extreme caution when handling gasoline.
VALVE SPRING
The force of the coil spring keeps the valve seat tight. Weak-
ened spring results in reduced engine power output, and often
accounts for the chattering noise coming from the valve mecha-
nism.
• Check the valve spring for proper strength by measuring its
free length and also by the force required to compress it.
• 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 the spring.
$ Valve spring free length:
Service limit: (IN. & EX.): 39.8 mm (1.57 in)
% 09900-20102: Vernier calipers
$ Valve spring tension (IN. & EX.):
Standard: 137 – 157 N
(14.0 – 16.0 kgf/36.6 mm, 30.9 – 35.3 lbs/1.44 in)
VALVE AND VALVE SPRING REASSEMBLY
• Install the valve spring seat 1.
• Apply MOLYBDENUM OIL SOLUTION to the oil seal 2, and
press-fit it into position.
( MOLYBDENUM OIL SOLUTION
"
Do not reuse the removed oil seal.
• Insert the valve, with its stem coated with MOLYBDENUM
OIL SOLUTION all around and along the full stem length with-
out any break.
"
When inserting the valve, take care not to damage the
lip of the oil seal.
( MOLYBDENUM OIL SOLUTION
36.6 mm
(1.44 in)