is being warmed up on the stand, because all the
cylinder head nuts are not accessible with the
proper tank in position.
See that the rocker box gaskets are intact and
replace the rocker box covers.
After tightening the cylinder head nuts with
the engine hot, recheck the tappet clearance at
some convenient time when the engine is cold.
7. Removal of the Valves
Remove the cylinder head and rockers (see
Subsection 6).
Using a suitable compressing tool, compress
the valve springs and remove the split conical
collets from the end of the valve stem.
Slacken back the compressing tool and
release the springs.
Withdraw the valve and place its springs, top
spring collar (and bottom collar if it is loose), the
end cap and split conical collets together in order
that they may be reassembled with the valve
from which they were removed.
Deal similarly with the other valve in the
head.
If the valve will not slide easily through the
valve guide, remove any slight burrs on the end
of the valve stem with a carborundum stone. If
the burrs are not removed and the valve is forced
out, the guide may be damaged.
8. Removal of the Rockers
See Subsection 6.
9. Removal of the Valve Guides
To remove the valve guides from the head
two special tools are required which can easily
be made.
The first is a piece of tube with an internal
bore of not less than 7/8 in.
The second is a mandrel about 4 in. long
made from 9/16 in. diameter bar with the end
turned down to 11/32 in. diameter for 1/2 in.
Support the cylinder head on the tube which
fits over the collar of the valve guide. Using the
mandrel, force the guide out of the head with a
hand press or by using a hammer.
To fit a new guide, support the head at the
correct angle and use a hand press and the same
mandrel. If a hand press is not available and the
guide is replaced by a hammer, use the mandrel
to prevent damage to the guide and treat with
great care.
It is necessary to re-cut the valve seat to the
correct profile and grind in the valve after a guide
has been replaced.
10. Removal of the Cylinder
Barrel
Remove the Cylinder Head (see Subsection
6).
Put the piston at bottom dead centre.
Remove the 1/4 in. nut above the tappet chest
and lift the barrel off.
When replacing the cylinder barrel, clean off
the joint faces and fit a new paper washer.
11. Removal of the Piston
Remove the cylinder head and cylinder barrel
(see Subsections 6 and 10).
With the tang of a file remove, the wire
circlip retaining the gudgeon pin on the timing
side.
Extract the gudgeon pin using Special Tool
No.E.5477 (use adaptor if necessary), having first
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