The Teardown

I rode The Norton to quite a few of the club events when the 2005 riding season started. It had problems though - heavy smoking and oil consumption, a knocking sound coming from somewhere in the engine on startup, and severe wetsumping. These bikes all wetsump (oil drainage from the oil tank to the crankcase when parked), but this one would empty the oil tank in just a few days. Definitely not normal.

In July, I bought an oil pressure gauge kit from my favorite parts supplier, OldBritts. I hooked it up and went for a test ride. The results were discouraging. The bike had decent oil pressure at startup, but when the engine warmed up the oil pressure went to zero.

So I decided to do a top end rebuild and to service or replace the oil pump. I had planned to do that work in the winter, but based on the gauge readings I felt the bike might not last that long. When I opened up the oil pump I found ground-up bearing fragments inside. That, of course, meant a full tear down and rebuild.

We pulled the motor and tore it down at the next Tech Day in August. The rod bearings were junk, the crank journals scored, the pistons had seizure marks, and the exhaust valves were burned and leaking. The oil consumption turned out to be caused by a bad hone job, which resulted in the rings not seating. And there was more shrapnel inside the crank's sludge trap. Oh, and the crankcase was cracked at the oil pump mounting area. The motor basically needed new everything.

With the motor out, it was a good time to go through the gearbox. Pulling the gearbox exposed a lot of peeling paint and rust on the frame. And when I removed the forks and triple clamps (the triples had peeling paint) I noticed the steering head bearings were shot. I decided I might as well take the bike down all the way and do a full restoration.