Hugh,

The point I am trying to make (well, one of them), is that many people do still regard the break-in as witchcraft and run their tapered-bore engines at a very slobbery four-cycle, which may damage it and will certainly shorten its life.

This ritual comes from the meehanite piston past and thinking that if it is good for the venerable cast iron piston, it must also be good for the tapered-bore. It is not and it is wrong!

For ringed engines, this hotter break-in is potentially damaging.