From somewhere on the internet archives I have found the repair manual for my bike’s obsolete early 90s press fit square taper bottom bracket. I have converted it to a pdf.

Perhaps it’ll be of help to myself or the few other owners of these bikes before they have to improvise pressing the spindle and bearings out. Somehow you would have thought the manual would have listed the bearing size or number. I suspect it’s a 6803 (17x26x5mm) bearing, given these old spindles are usually 17mm and the bottom bracket shell seems to have unusually small outer diameter. I probably won’t get around to removing the crank arms until maintenance is required, so I hopefully won’t be reading the seals for the number anytime soon.

At least it looks to be made of standard parts… just the frame’s bottom bracket is machined to directly take the bearings. Certainly a bit of an oddity.

Best of luck to anyone working on these old frames. They still ride great.