I would have thought , If the liner fitted right , It would not matter ?.
No doesn’t matter. This one was ok and I ended up using it on my Mongrel Comet project. I popped the liner out to see what sort of crap was built up in there ( check fit) and also deal with the oil feed hole in the liner which like every other one I’ve measured was too high. The muff seems to be darker since I installed it, so suspect it is still oozing slightly. Would be nice if it waited until it at least until it go some engine heat! Originally the plan was to paint that engine black, but the cylinder muff kind of put me off that track.
I’m a little concerned Robert hasn’t responded to my wisecrack about baby powder. He’s about twice my size, which is what I would normally worry about, but with social distancing rules he’s likely loading a projectile.