Went flying yesterday with my neighbor (pvstjr). He had two planes. A UCD 60 with a OS120AX and a Twist 60 with a OS91FX. After one of the flights of the twist 60, Immediately after shut off, I reached down to pick up the plane and place it on the starting stand. The end of the crank was cold and then I felt of the crankcase and it was cold also. The OAT was around 70 degrees F.

The twist 60 is a "Cheek Cowl" type plane with basically an exposed engine.

I was surprised at the cold crankcase after a 15 minute flight. I had touched the engine immediately after shut off so there was no post run heat soak.

I had a Slow Poke with a OS 52 but failed to feel of the engine. On the Slow Poke, though the engine is exposed, the bottom of the crankcase is basically enclosed. My friend placed my plane on the starting stand.