Triumph Unit 650 Gearbox

Thrust Washer Locating Peg Repair

In 2018 I tore down Bonnie's gearbox because I found quite a bit of bronze 'sludge' in the outer cover.

After I removed the gear cluster I noticed that the DS thrust washer locating peg was not only damaged, but protruding from the case insufficiently. How the peg came to be damaged and driven into the casing I can't say for sure, but it was almost certainly a ham-fisted needle bearing installation by yours truly in 2016. I'd had a proper drift fabricated with a notch for the peg, but evidently I still managed to blodge the job.

After losing lots of sleep over this, I took the engine to Bob St-Cyr, a local and very talented millwright, and he fabricated a jig which he used to drill another hole and installed a new peg after grinding off the old one.

Later, after several unsuccessful attempts at installing the layshaft and mainshaft bearings, I returned to Bob's shop with the engine and he pressed in the bearings in no time at all with an industrial 50-tonne hydraulic press.