Gee, RC-Fiend, you manage to build and fly a Lanier Shrike (with LOTS of help) and suddenly you're an expert? The analogy is so totally non-sequiter that it borders on ludicrous.

MANY things govern engine RPM. Prop diameter, pitch, blade width and blade airfoil thickness, blade shape, engine reserve power, and even airframe parasitic drag. To make a blanket statement that a larger diameter prop lowers RPM is totally in error.

Confucious say: Man who make analogy of spinning on barstool must spend lot of time researching this.

Dr.1