The Ukey 35 will definitely fly well on a good 25. I flew mine with a SSW Thunder Tiger 25 turning a cleaned up RevUp 9X4 on 61' x .015 lines (measured from the handle to the bell crank). It was a great combination! It also flew very well with the Fox 35 described below and the difference, for my purposes, was insignificant.
I fly my Ukey 40 on a GMA Custom Fox 35 with stuffer backplate and hemi-head, 10x5 BY&O (Brodak), on .015 lines, 61' from eyelet to eyelet (I added permanent cable leadouts to this one). It, too, is a great combination. I am going to try the TT 25 on the Ukey 40, but, probably, with slightly shorter lines to start with.
Regarding the Ukey 40/Fox 35 combination let me make a couple of observations that might be helpful. First, Jim Pearson suggests that the plane balance on the spar about half way between the fuselage and the wing tip. At first, mine balanced about a 1/2" behind that spot even after I changed to single peg landing gear to two wheel gear. While it certainly was flyable, it did want to hunt. The addition of just 3/4 oz. to the nose greatly improved that. Second, with the relatively long lines it was necessary to add 1/2 oz. of tip weight to get the wings level upright and inverted. However, the plane is a pre-Jim Pearson version and I do not know whether Jim has changed anything. I will find out when my new Ukey 40s arrive.
I am a retread who is using the Ukey 40 to thrash my way through learning the pattern. It was a great thrill for me when I did my first vertical eight a couple of weeks ago. In my opinion, the Ukeys are a boon to folks in my situation. I learn new stuff on my Ukey, then haul out one of my kit-built or scratch-built planes and try it on it. Try a Ukey; you'll love it, especially since in the world of model airplanes it is so ugly that it is almost cute.
Topic: Question about the UKey model engine size (Read 1277 times)