My Arrow's piston bosses were so worn the gudgeon pins were rattling like a bag of spanners so I've had to go for a +.020" rebore with Suzuki pistons. A shame as the bores were fine.
I know that ordinary mineral oil is recommended for running in four strokes - would the same be true for a two stroke (this is my first since a couple of MZs on the 1970s). I don't want to spend the rest of my life running it in, but neither do I want to lay down an Atlantic Convoy style smokescreen for the next couple of years.
1962 Ariel Arrow
1931 Sunbeam Model 10 (for the moment)
1992 Honda CB400 Super Four ("modern" bike)