Not many pilots here in the USA use the TT engines (at least locally). I'm only familiar with one that's an 0.80 4~stroke a friend runs and it produces good power and has been reliable over several seasons. Ther are a number of posts regarding the 0.40's used for pylon racing and the mods needed for reliable running. Check out the engine forums for additional information on the engine. Digital servos are really nice in this kind and size plane. Holding power is what you are after along with good centering. A servo that doesn't come back to center will drive you nuts. As with most ARF's there is a need to make a few "adjustments" as you need for the SFG's. Post some photos if possible so we can see the exact nature of the problem. A call or email to Horizon will get results or send a PM to Mike McConnville (the designer) through his forum here on RCU. There is a really great review of this plane in the Jan/Feb 2006 of Dick Hanson's version with an Evolution 26cc gasoline engine on a tuned pipe if you can get a copy of 3-D Flyer magazine. Let us know how it flies for you.
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