How to start the RCV
Ed
First of all decrease your oil content in your fuel to 14-16% max. Than raise the Nitro content to 15%. Than as I recommend in all the posts, put on a Zinger 18x12 or 18x14 2 blade prop, and try your Mustang again. You changed too many variables from the norm. to make an appropriate comparison in flight. You fly your YS on 20/20 fuel because that is EXACTLY the fuel which YS recommends. If you run less oil than 20%, that would mean that you increase performance. RCV recommends 14-16% oil MAX not 18%, so you are exceeding the oil content hence hindering performance. Also you are running only half the Nitro of the YS. Raise that to 15%, which is the maximum recommended by RCV. Such as 20% is the maximum recommended by YS. Try this combination, than tell us what you think. You should find a considerable difference. The RCV is designed and intended to turn a large and wide prop very slowly. You are turning the YS at around 9000 revs with a 7" pitch prop and only 3 blades. If you had no slippage at all, your airplane could reach a maximum in-flight speed of 60 mph. You are turning the RCV at only 4900 revs with a 10" pitch prop and four blades, which gives you a maximum in-flight speed of 46 mph. this is simple math. Put a Zinger 15x14 three blade prop with rounded off and thinned out prop tips on it and see what you think. Plus You have decreased efficiency by about 10* by adding an extra blade to the combo. Next time when you make comparisons, change only one variable at a time. this being the Engine/fuel combination.
Otto Kudrna, RCV Tech Support
PS Take it from someone who has about 600 hours on these engines.