BSA Winged Wheel W1 Instruction Manual page 21

then included in the literature provided with the
unit, but a summary of information is provided
here. The ma.kers' type reference is B.S.l9.
A rota.ting flywheel with cast-in magnets is used,
and this revolves a.bout pole pieces and coils fixe.(l
to the sta,tor plate which is secured to the crankca,se
by two screws. (Check these screws mca§ionally
and keep them tight).
1`he contact-breaker cam is formed by an interna.l
e`tensi()n oí the flywheel hub. See ma,kers' booklet
for illustration.
Contact Breaker.
AÍter removing the magneto cover, the contact
breaker is visible and accessible through one oí the
slottcd holes in the flywheel. It is important tha.t
a,t a.ll timcs the contact breaker points (contacts)
should be free írom oil or grease. To clean. use a
pïece of fine emery cl()th a,nd after use wipe with a
petrol moistened rag.
Contact Breaker Setting.
The contact breaker gap is set a.ccuraitely before
leaving the worki at.018in., but occasiona,lly ad-
justinent shoulcl be made to mainta.in this. Adjust-
ment is necessa,ry owing to the wear oí the lever
lieel. It is a,dvisable to check the gap a.t 500 miles
scrvice an(l thereaíter when full decarbonising is
undertaken (2,000/2,400 miles).
To Adjust.
First re")lve the flywheel so tha.t the contact
lcvcr is liftecl to its highest position on the cam;
tlic" h"scn the atlJ"ster contact pla.te fixing screw
(which is immedia,tely under the fixed contact) just
suÍ`Iicient to a.llow the contact plate to move with
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pressure from a screw driver to the correct position
oÍ.Olsin. between the contacts, then tighten the
fixing screw.
Timlng.
It is essontial to set the contact breaker maximum
gap (see a,bove) beíore a,ny a,ttempt is made to
"time" the magneto. A Woodruff type key. fitted
in the seati": in the taper end of the crankshaft,
lmates the flywheel and cam ror approximate timing
position.
Final exact timing ís made by setting the stator
plate with the fixinÍ;y screws central in the slots.
Turn the flywheel clockwise until the piston has
tra.velled 5/32in. down from its top-dead-centre
position, and check if the contact breaker points
aire just pa.rting (use a.OO2in. feeler ga,uge). If the
points are more than.002in. open, loosen the sta,tor
plate screws and tum it a fraction anti-c]ockwise,
re-tighten and re-check piston position and points
opening. If the points have not opened at all,
move the sta,rter plate in the opposite direction
(clock`rise) amd re-check.
The adjustment required will be very small.
BE SURE TO TIGHTEN THOROUGHI_Y
THE STATOR PLATE SECURING SCREWS.
Lubrication.
Every 2,000 miles apply a few drops of thin oïl
to the felt cam lubrica.tor.
At maior overhauls, remove contact breakcr
lcver and very lightly smea,r the pivot with thin
oil.
Hlgh Tension Cable.
If this shows signs of cracking or perishing it
should be replaced by use of 5mm. or 7mm. cable
(P.V.C. covered recommended). To releaée ca,b]e
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