I flew my 2nd Primary Force on Tuesday Oct 9th. Power was a K&B Sportster 20. The plane flew well did not need any outboard weight though,strange. Prop was a 9/5, Fuel PowerMaster 10/29 used the Kavan tank which I've always disliked.Line tension was very good, rounds were good, squares are a little soft but generally the plane flew very well.
There were two other P/F there. One with a TT36, too heavy and does not impress me at all. Second one had an OS 35S on it and was flown by a low time pilot so we didn't see any maneuvers but it flew very well.However it needed /had a trim tab on it, should take it and do some tweaking on the wing with a heating iron.
My first one had a K&B 28 and I truly enjoyed it till it met it an unfortunate premature end. Using the 20 was an exercise simply to see if there would be a significant difference in the power. There is obviously a difference but the 20 does an admirable job.The overhead eights didn't suffer from lack of line tension and the wingover was firm through the maneuver.
I like models that have only moderate pull, existing medical condition makes stump pullers out of the question, and this is a very nice combination for me.
dennis