So far, my sportster .65 has been a decent engine... though changing fuel tank styles took a bit to get working right but otherwise powerful enough to do what I needed it to do. The .65 sportster on my boat will turn a 13x6 at roughly 10,200-10,400rpm.

The all-castor fuel these engines like is tough to find at a retail store. Almost nobody carries it nor will they order it. Closest thing I found was 1/2A fuel which has too much nitro and only comes in 1/4 pint or 1/2 pint bottles.

I'll be making my own fuel and if anyone wants some all-castor fuel, let me know.