I only have one four-stroke engine, an OS 26FS I bought from a friend, who swore it was new when he got it, and he only ran it on the bench to check it out. It is still un-run by me, but I do oil it regularly with Marvel Air Tool oil, and flip it over a few times to circulate the oil.
Ernie, Your name rang a bell, so I checked the link in your message, and found the most wonderful collection of photographs I've seen in ages! We lived in Federal Way for almost 30 years, but moved to Portland after I retired, to be near our youngest granddaughters. Also flew R/C with the Boeing club, and the RAMS club for the last ten years we were there.
Guess I never noticed the handling problems with the Mach III, but the straight smooth road I was on, and keeping the front wheel off the pavement most of the time must have masked the problem. <G>
Lots of talent on this forum, and I wouldn't be surprised if many of you are also into target shooting, and reloading?
Bill