Wiring Diagram for Triumph, BSA with Boyer Ignition Wiring Diagram for Triumph, BSA with Boyer Ignition . Wiring Diagram for Triumph, BSA with Boyer IgnitionHonda Motorcycle Electrical Wiring Diagram .[PDF] BOYER BRANSDEN ELECTRONICS LTD KIT00052 MICRO-MK.4 IGNITION SYSTEM FOR TRIUMPH/BSA 12V TWIN CYLINDER MOTOR CYCLES WARNING: THIS UNIT CAN PRODUCE HIGH VOLTAGES, ALWAYS TURN OFF BEFORE wiring, battery in different positions; thus it may be necessary to modify If an old Boyer Bransden ignition unit is being replaced with a new one, it is ad- Vintage Bike Magazine » How to troubleshoot a Boyer ignition How to troubleshoot a Boyer ignition. IMPORTANT. Most Lucas alternator rotors have timing marks, lines on the rotor, in two locations. These are a hold over from the ill fated Triumph Fury and BSA Bantam and its 180° crankshaft. See wiring diagram for your bike downloadable below.