Jon, you are not alone. There were a lot of people looking at that bike. Mostly they were old silverbacks like us.
Pete, the standard bike is rare now. This Honda and the Triumph Bonnevilles are about the only ones left.
A while ago I was looking for a new oil. The price is raised on the Mobil 1 to the point where I have no incentive to use it. The people at Cascade Moto Classics help me a lot and I want to use an oil they sell. It is good promotion for them. This narrowed my choices a bit - Mobil 1 or Silkolene. Mobil 1 never gives a detailed and specific answer. The Silkolene company has the opposite approach and this is the deciding factor for oil choice. Advice I have from Silkolene is the Pro-4 10W-40 is a 50% ester, 50% PAO mix, it was their top of the line oil till a few years ago, it comes in 10W-40, and it is recommended for street use. The also make Pro-4 Plus 05W-40, a 75% ester, 25% PAO blend, and it is their current premium oil. It is more expensive. The added protection from the higher ester content makes it their recommended oil for racing. They suggested that I do a dyno comparison with the two oils to see which one makes the most power. The new engine will be tight this year and I will use the Pro-4 Plus, after that the Pro-4 will be good enough.
A friend in my youth had BSA 441cc Victor Shooting Star. It was a pretty bike with its red and white fiberglass tank. The Victor engine was developed from the Triumph Tiger Cub motor and it was as reliable as a hand grenade. An oil seal would pop out from the engine when he rode it hard. Oil went everywhere. We traced this problem to excess crank case pressure. Combustion gas blow by past the rings pressurized the lower end when he was riding hard. The standard BSA engine breather could not bleed the gas out in time to prevent trouble. This pressure also hurts performance, I learned later.
The job here is installing an extra breather on the filler hole where the oil is poured into the crankcase. The plug has metric threads and I could not make one on the lathe. It was hard to find a plug that could be modified. Finally, I found one, it is Part # NBCA-1050S, LCF Custom OIl Filler Cap, Silver, see
www.lcfabrications.comSome sort of baffle is needed to keep the oil that flies around in the engine from going up the breather pipe. I drill four holes in the bottom of the plug and one big one in the top. Hopefully this will catch the oil and it will drip down rather than blow up through the pipe. The brass spigot for the hose is turned from a piece of 1/4 inch ID brass gas line with pipe style threads. The rubber hose is from the Triumph pollution control system that almost everyone removes, often called the "octopus." A PCV valve and oil catch tank will be made, too.