RE: TT 61 GP leaning out?
Hi!
When an engine gets a little worn (Piston to cylinder fit not as tight ) then the carbs fuel sucktion ability becomes not as good as compared to when the engine was new. Then it's important that you do whatever you can to help the engine suck fuel! That's your problem!
To have an engine function properly includes using 10-15% nitro fuel, A 12x6 ,13x4,13x5 or 14x4W Prop( Best props are APC and RAM). Medium hot glow plug like a OS 8 or Enya 3 glow plug (No idle bar plugs please). 12 oz tank (not bigger)! and probably in your case ...get rid of that small silencer that robs power and use the standard TT silencer which probably have less exhaust diameter outlet compared with the after market silencer you have on now. A silencer with less exhaust area gives much better fuel draw!