lntrod uction
This manual has been compiled to provide comprelrensive service information for the B.S.A. orvner
and lor the workshop fittel rvishing to carry oLrt either basic maintenance or major repair work. It is written
in great detail. but because of the specialised skills and equipnlent required to carry oLrt some of the rvork
described. the irrexperienced owner is strongly advised to consult his dealer whenever he is irr doubt as to
his own ability to calry oLlt a satisfactory job.
The manual is divided into sections dealirrg rvith tlle major assemblies and these are sub-divided into
the individual operations reqr"rired for maintenance and repair. It is hoped that by using this arrangement.
the manual \yill be lound most uselul as a quick rvork of relerence even to the skilled mechanic.
All information and data given in this nlanual is correct at the time of publication but because of our
policy of constant development. changes in specification are inevitable. Anyone finding this manual to be
at variance with the niachine in his possession is advised to contact the Service Department. where up-to-date
intbrmation will be qLrickly provided.
ENGINE AND FRAME NUMBERS
Both engine and frame nunlbers. together with prefix and sr,rffix letters, must be quoted in full on any
correspondence relating to the machine or on any enquiry re_earding this manual, to either the dealer or the
Service DepartInent.
The engine number ("A") is stamped on the left-hand side ol the crankcase immediately below the
cylinder base. The frame nunlber ("8") is stamped on the prop-stand lug, or. on later models, on the left
side of the steerins head-
N
a
F00t0t B25T
FrG. l, Engine and frane nunbers, Page 9
