A few days ago I ran this engine comfortably at 9 1/2 to 10 RPM.
I wanted to slow it down to 8 RPM which was done before. However I wasn't too optimistic.
It hadn't run this slow since relocating to the new Office of Steam 3 years ago.
Then I oiled it up good and left it running at 10 Rpm for a couple of days.
Today I tried again and to my surprise and delight... I got it slowed down to just 7 RPM...!!!
Enjoy,
Gil