PRIMARY
DRIVE
SECTION
CI3
INSPECTION
OF
PRIMARY
DRIVE
COMPONENTS
C
(1)
Inspect
the
primary chain for excessive
wear
of
the
rollers and pivot
pi
ns, and check
that
the elongation does not exceed 1t%- To do
this, first scribe
two
marks
on
a flat surface
exactly 14 In. (35.5 em.)
apart.
then
after
degreaslng
or
washing
the
chain
In
kerosene
(paraffin), place
the
chain
opposite
the
two
marks.
When
the
chain
Is
compressed
to
Its
minimum free length
the
marks should coincide
with
the
centres
of
two
pivot pins 32 links 'Ipart.
When
the
chain
Is
stretched
to
Its maximum
free length
the
extension
should
not
exceed 0.2
Ins.
(6.25 mm.).
Inspect
the
condition
of
the
sprocket
teeth
for
signs of hooking and
pitting.
A very good
method
of
Indicating
whether
the
chain
Is
badly
worn
or
not
Is
to
wrap
It round
the
chainwheel and
attempt
to
lift
the
chain
from Its seating
at
various
points
around
the
sprocket. Little
or
no
11ft
Indicates
that
both
the
sprocket
and chain
are
In
good condition.
If
the engine sprocket
Is
a
tight
fit on
the
cran~
shaft,
there
is
no cause for concern,
as
such a
fit
Is
to.
the
best advantage.
(2)
Check the fit between the shock
absorber
spider and the clutch shaft splines.
The
spider
should be a push fit
onto
the
splines and
there
should not
be
any rotary
movement.
Similarly check the fit of
the
engine
sprocket
splines on the crankshaft. Again
there
should
not be any rotary
movement.
(3)
Check
that
the shock
absorber
spider
Is
a
good working fit
In
the
Inner and
outer
retain-
Ing
plate
and
that
the
arms of
the
spider
have
not caused excessive score marks
on
the
Inner
face
of
the housing. Check
the
working
clearance
by
assembling
the
shock
absorber
unit without
the
rubbers.
replace
by
a single connecting link and
Inner
link
as
shown
In
(4).
SECTION
CI4
REAR
CHAIN
ALTERATIONS
AND
REPAIRS
If
the chains 'have been
correctly
serviced, very few
repairs will be necessary. Should
the
occasion arise
to
repair, lengthen
or
shorten
the
chain, a
rivet
extractor.
as
shown
In
Fig. cn. and a few
spare
parts will cover
all
reqUirements.
(4)
(I)
~~e~~e~~:~~-~'
;:;;~_
~g~_~.
ii"'_:t::~~~:;!;·!JI!~~.
To shorten a
chain
containing
an
even number of
(5)
pitches, remove
the
dark
parts
shown
In
(1)
and
~
replace
by
crank
double
link and single connecting
link
as
shown
In
(2).
(2)~
To
repair a chain with a broken roller
or
Inside
link, remove
the
dark parts shown
In
(5)
and
replace
by
two single connecting links and one
Inner link
as
shown
In
(6).
(3)~~
'(6)_
To
shorten a chafn
containing
an
odd
number
of
~
~
pitches remove
the
dark
parts
shown
In
(3) and
Fig.
C11.
Rear chain
al'e""lons
•
.
~
:
..
C11
To Next Page
Loading...
