Using the Degree Wheel to Establish Ignition Timing By David Porter, Customer and Technical Support at The Bonneville Shop      You have finally decided to convert your 1967 Triumph Bonneville to electronic ignition. The instructions tell you to remove the points plate and mechanical advance unit. Not to worry, once the old ignition parts are out of the way, you can start retrofitting your new modern ignition. Once the…

Have you seen our blog on Cam Timing Notes? Dave has written up a companion history of the Camshaft.   The Brain of Your Triumph B Range Engine- the Camshaft By David Porter, Customer and Technical Support at The Bonneville Shop      This overview of the camshafts and their function in the Triumph 650 and 750 engines is intended to help familiarize the engine builder with the evolution and applications…

By David Porter, Customer and Technical Support at The Bonneville Shop During the late 1960s, the BSA Group was busy developing the next generation of Triumph and BSA motorcycles at a leased 17th-century mansion in Warwickshire, known as Umberslade Hall. Situated nearly equidistant from Redditch, Small Heath, and Meriden, the research and development facility was the epicenter for the design teams to update both ranges to the modern specifications needed…

12 Volt Charging System Diagnostic Guide By Mike Grage, Customer and Technical Support at The Bonneville Shop Quite often we get questions about electrical diagnostics, most common is the charging system and how to test rectifiers. Whether it is a solid state or the factory diode pack, they work the same.  The first bit of advice I give less experienced technicians is to think of electricity like water, electricity flows…

Layshaft Needle Bearing Installation Tool: TBS-0041 By David Porter, Customer and Technical Support at The Bonneville Shop           When using our TBS-0041 layshaft bearing drift tool, be sure to place the 57-1607 thrust washer on the locating peg in the gearbox housing, as it sets the depth of the closed-end 57-1606 layshaft needle bearing. I like to freeze the bearing for an hour and then heat…

Carburetor Mounting O-rings: 622/101 Thin vs 70-9711 Thick By David Porter, Customer and Technical Support at The Bonneville Shop Frequently, confusion arises over which carburetor flange mounting O-ring should be used when fitting Amal Concentric carburetors to Triumph twin-cylinder engines, or whether an O-ring should be used at all. We offer 3 different carburetor O-rings: the 244/1048, as used on the Amal Monobloc carburetors, and the 622/101 and 70-9711 O-rings,…

Creating a Custom Made Cable By David Porter, Customer and Technical Support at The Bonneville Shop From time to time we encounter an inquiry for a throttle or choke cable that is not available as pre-manufactured by our suppliers. There can be a number of reasons for non-standard fitment of cables, such as a change in handlebar height or width, the use of an aftermarket throttle twist-grip, or when a…

Piston Ring Replacement By David Porter, Customer and Technical Support at The Bonneville Shop From time to time, we receive reports from customers replacing piston rings on their Triumph engines, that the measured ring end-gaps appear to be out of specification. There can be several reasons for this perception. Sometimes, the technician performing the job simply doesn’t know the size of the pistons presently in service in the engine. Usually…

Fettling with your Vintage Brit Bike By David Porter, Customer and Technical Support at The Bonneville Shop This interesting Triumph Service Bulletin, issued on 11/9/1973, seems to confirm what many of us have known all along- sometimes you have to massage parts to make them fit correctly, or slightly modify them to improve fitment. Pattern parts originate from all over the globe, and are manufactured to varying tolerances. We find…