15/03/2026
Yesterday I had the privilege of a visit from an old guy who turned up on a Norton Motorcycle. I had never met him until now. He had hunted me down through old contacts, in search of a job that I have done for over 37 years. I have no idea how many I have ever done; it would be in the hundreds. I would have to go back through my old text book diary paper records, it was pre computers. The original customer ran a bike shop for Nortons, Triumphs, BSA, etc. He has long since retired, so sourcing parts for old bikes has become a big problem if you are into building and restoring motorcycles. Over the decades, I machined many reproduction parts for these old bikes, which I still retain all the hand sketched drawings with dimensions, all the CNC program codes, gauges, jigs, etc. Again, it was pre computers, so no fancy CAD/CAM back then. It was all worked out using this ancient and obsolete concept called “AI” (actual intelligence). It was in abundance once upon a time. So, doing yet another batch of these Norton Commando cylinder head stub repair bronze helicoils was a walk in the park. I never thought I'd be doing them again, but here we are. There must be a few old Nortons being resurrected. I enjoy doing these sorts of jobs because I know they will end up on some old bike project out there somewhere and once that guy enjoys his 1st post build ride, that smile will be priceless. Building and riding my own is where most of this work began. These are machined from standard grade LG2 Bronze, they are for repairing the aluminium casting where the exhaust port thread has worn away. The cylinder head is mounted in a jig and the old thread bored and threaded to suit these new bronze inserts. I do not do the heads, only these bronze inserts. The threads are 14tpi external and internal 180 degrees opposed to create a very thin wall section. This job had me reflecting on the many years I machined parts for old Muzz and hope he is doing well in retirement.
