ORIGINAL: MOTORMAN37
I guess if you have never heard about heating the cylinder head, you have never been around a Tight True ABC engine. A little heat with a heat gun on the Head is done all the time ........
I have and have had many "Tight True ABC" engines. I remember a ST.61 ABC that really squeaked. Also a Rossi. I've heard of the preheating gig before, just have never found it necessary. Just broke in a friend's OS .46 AX. We did it by the manual (his choice) and didn't need to preheat it. It started easily and ran well.
The TH .75 owner's manual has very detailed instructions, including break in procedures. It doesn't recommend preheating.
One thing universally true in this hobby; there are as many opinions as there are, er, people. Doesn't mean any of them are right...or wrong.... just lots of them...............
CR