Suzuki RM-z450 Owner's Service Manual page 101

• 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
• 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.): 35.8 mm (1.41 in)
# 09900-20101: Vernier calipers
" Valve spring tension:
Standard (IN. & EX.): 146 – 168 N (14.9 – 17.1 kgf)/
VALVE REASSEMBLY
• Install the valve spring seat.
• Apply engine oil to the stem seal 1, and press-fit it into posi-
tion.
Do not reuse the removed stem 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 stem seal.
% MOLYBDENUM OIL SOLUTION
& WARNING
30.9 mm (32.8 – 37.7 lbs/12.2 in)
CAUTION
CAUTION
CYLINDER HEAD, CYLINDER AND PISTON 6-16