The Sparking Plug - BSA B31 Instruction Manual

thc spindle
slightly
by
means
ofa
to@ny
bar
at
C. Slacken
ofr
the hexagoD
B on
the left-hand side
of
the
hub
dren
screw the adjusters
D in or out
as
the
case
may
be,
until
the
chain
tensioD
is correct, with not
less than
i
in. total
up-and-do\rn movement,
at the
ceDtre
of
the bottom run
of
the chain
*itlr
the
machine oD
its central
stand.
so
that the rear
wheel is
in
its
lowest positiotr.
Resr Chain Adiurboe[t (Comp. and
Swinging Arm
models). Uascrqw the spindle
4
Fig.
8,
slightiy with
a
tomDy bar then
slacken
ofr
the hexagon ,4 oD the left
hand side
of
the
hub,
Release the locknuts C and søew
the adjusters
D in or
out
as the
case
may
be,
until
the
chain
ten3ion is correct,
with not
less
than
I
I in.
(Comp.
l
in.) total
up-and-down
movemeDt
at
the
centre
of
the
bottom
ru!
of
ihe chaio.
To allow for
any variation
in
chain
tensioD
the
wheel
should
be
rotated by hand
until
the tightest
pointis
fouad,
with
the wheel
in
its lowest
positiotr.
Front Brake
Adiustmeot
The lenSth
ofthe
brake cable can
be
altered
at
its lower
end by means
of
a
knurled thumbnut
on
the cable
stop,
(For Gold
Står Racing,
see HaDdlebar
lcvers, page 57.)
Resr Brake
Adiustment
Finger adjustment is
provided
at
the end of brake rod.
Do not
set
the blakes
too
closely, since,
particularly
in
tho
case
of the front brake, its action
may
be
too power{ul.
Any friction
between
lining
and drum
will
obviously
impair
the macbine's
pedomanc€.
In
addition,
if
carded
to
extremes, the heat may melt the grease
in
the hubs and
this may
find
its way
to
the brak€
linhgs. (For lub
cation
see
page
16.)
Centralising
(7in.
Brakes
only).
Slacken
the
nut on
thc
brake cover
plate,
thus loosening the fulcrum
pin
in
its
slotted
hole. Apply
brake, when fulcrum
pin will
auto-
matically c€ntralise the
assembly, and keeping
lhc
brake
on, finally lock
up
the
nut.
(See
also page
19.)
Brrkc
Crm
Spindlcs.
Thesc
arc lubricated with
oil
scc
fugc
lli.
32
Sprking
Plugs. The
spdking
plug
is
of
Sleat
importance
in
satisfactory engine
perfomalce,
and every care
should
be taken
to fit
the correct type when replacements
arc
necessary. There
is
little
1o
be gained by
experimenting
with
different plugs
as the
make and
twe
fitted by u$
as
official factory
equipment
is
best suited
to
the
rcquire-
ments
of
the
motor. This is Champion Type
No.
L10S
(competition
models
NA8. Gold
Stars,
see
page 56).
Fis.14,
The
spa*ing
plug
Remove each sparking
plug every
1,000
miles
(1,500
km.)
or
so
for idspection.
lf
the
carbu.ation system is
in
correct adjustment
the
sparking
plug points
should
Emain
clean ahnost
indefinitely.
An ovel- ch mixtwe
fiom
the carburetter
will,
however, cause
the fomation
of
a sooty deposit
on
the points, and, later, on
the plug
end face
(!s
upper view,
Fig. 14).
If
thereforc such
a
deposit
is
found, clean
it
off
carefully and
check your
carbuletter.
The continued use
of leaded fuel may also
evettually
produce
a deposit
on the
plug-this
time
of a geyish
colouf.
3l