This Instruction Book has been prepared to supersede the previous edition F. 236 /2R., and in compiling it we have dealt with various dismantling and re-assembling operations in greater detail and have also included more information on the Carburetter, Magneto, and Electrical equipment, than was included previously.

Wherever possible, reference has been made to points which differ, on current models, from the specification of some old pre-war machines still in commission. Should any point not be fully understood, however, we will gladly reply to any enquiries provided that these give the Engine Serial Letters and Number of the machine to which they refer.

A careful study of the contents will be worth while and should enable the owner (be he novice or expert) to maintain his machine in that state of efficiency which it is impossible to retain without attention to those simple, but none the less im-portant, adjustments and lubrication details which are described in the following pages.

SERVICE DEPARTMENT.

F.236 /4R. January, 1950.