I ran the Tanaka yesterday. It started easily and idled real well. It turned a master airscrew 18x8 @ 6300 RPM, on 32:1 fuel mix. I think with an APC prop, and 50:1 mix, It might turn 7000. The only "issue" is the play in the crankshaft. At idle, you can see it wobble, it smooths out some at higher RPM, but I don't think this is a very good design. The engine looks real nice, and I had high hopes, You can see I did a lot of grinding on the flywheel, on the front and backside. It's seems fairly light too, 47oz as you see it here. The internal parts look real good too, I don't think it has much time on it, after cleaning it up, everything looks new, and fits well, It's just a poor design in my opinion.