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Tech Corner

Technical Q and A for classic motorcycle maintenance and repair.

BSA Electronic Ignition

Motorcycle Classics tech expert Keith Fellenstein

Editor’s note: If you’re having trouble with that old Suzuki, BSA or BMW, Keith Fellenstein is your guy. From motorcycle tuning tips to detailed motorcycle engine repair, he can draw from a wealth of experience to help guide you to success. Send questions to: Keith’s Garage, 1503 SW 42nd St., Topeka, KS 66609, or send an e-mail with “Keith’s Garage” as the subject.

Electronic ignition

Q: Aloha. I have a BSA A65. It has an electronic ignition installed on it. It was running fine until my son started experimenting with it. The magnetic pickup was removed and he removed the carb. I have installed a new carb and reinstalled the magnetic pickup. The wires are all correct according to the wiring diagram that is under the seat. I need to know how to get it back to basic timing so that I can get it running again. My legs are worn out from kicking it over with no luck. Can you help me please? — David Arthur/Hawaii

A: Not knowing the brand of electronic ignition, it’s hard to give exact directions, but this should get you close enough to get fire. Let’s assume you have a Boyer electronic ignition, as they are the most common ignition used on old British bikes. Pull the spark plugs. Turn the engine over using the kickstarter or by turning the rear wheel with the bike on the centerstand and the gearbox in second gear and line up the full advance mark on the alternator rotor with the marker on the outer primary case. Install the magnetic rotor on the camshaft end under the points cover and finger tighten the fixing screw. Place the pickup plate over the rotor, with the plate centered on the screw holes, so you have equal range of adjustment both clockwise and counter-clockwise. Rotate the magnetic rotor under the pickup plate until the magnet is centered under the hole in the pickup plate. Take care not to rotate the engine, just the magnetic rotor plate. Tighten the fixing screw. This should be close enough to start the machine, after that you will need to check the timing with a strobe light to be accurate.