John,
The minimum static/take off rpm required by Rotax (per service bulletin ) is 5200 rpm. By setting the pitch setting on the Kiev prop to acheive this I got less than 80 mph @ 5000 rpm in cruise. The Warp gave me 5300 static and about 88 mph in cruise at 5000 rpm. So in fact the Kiev achieved almost 10mph slower cruise speed. The Kiev prop I first received was not correct for my engine and I sold it to a friend for his 100hp Paradise. They are getting better results from the Kiev.
However,I purchased and now have mounted the correct Kiev for my engine. It is about 3 inches shorter in diameter . When set at the proper 5200 static the performance is about the same to slightly less then my Warp as far as speed goes. (close enough) That is not the only factor however. Besides its beauty it is increadibly smooth,like a turbine. It is over a pound lighter and appears to have solved my "run on " problem with my engine. When I would shut the engine down on occasion the engine would turn backwards for several revolutions requiring me to inspect the clearances on the valves for air in the lifters. This is a real pain !! and was driving me nuts as it happened several times. So there are more factors than just cruise speed.
I feel the reason I am not getting the increased speed is because of the radial cowl. The twist on the Kiev prop starts earlier than the Warp. I believe it is forcing alot more air into the cowl and that causes more drag. My oil temp confirms that as the oil cooler is close to the hub and the temp is now about 10 - 15 degrees cooler than it was (same temp conditions) due to the increased airflow. With a smooth cowl it would appear that more airflow would go around it thus less drag and more speed.
As mentioned earlier ,my neighbor keeps commenting on how much quieter the Kiev is vs the Warp ,on take off.
Overall I am very happy with the Kiev. It's a beautiful thing and sure compliments the airplane I think. And at least so far, when I shut the engine down I don't have to worry about it turning backwards.
Dick Maddux
Fox 4
912UL (80 hp, 2.27 gear ratio)