RE: 4-stroke eng. for cgb cub
G'day
I have two Goldberg Anniversary Cubs. Both are covered in Solatex. One is quite old. The original owner started building it with the idea of putting an OS 70 Surpass but did not finish it. When I bought it, I finished it, put a Surpass 70 in it and flew it. It was massively overpowered and the 70 is quite a heavy engine. It had two modes - less than 1/3 throttle was scale mode and any more was Spitfire Mode. I have since had several four stroke engines in it - an early OS 40FS (not quite enough) an Enya 41, similar to the OS 40 but enough for scale like flight but not a lot in reserve, an OS Surpass 52 (currently) a nice balance of weight and power, an ASP/Magnum 61 - slightly more power than the OS and also very light and of course, the original 70 Surpass which was too powerful unless you want to do lots of aerobatics.
The 52 OS is ideal though I suspect a Saito 45 or en Enya 53 would also be OK.
My second Cub was built late last year and is painted up as a Grasshopper but in Australian WWII colours. It has a Saito 90TS twin. It has about as much power as the ASP 61 (perhaps a little more) but is considerably heaver than the singles except the OS 70. I did not need to add any weight to the plane to balance it. It flies the plane very well and I gather it has enough power to handle floats should I ever want to. It also really sounds the part and is not a difficult engine to handle. The 60T twin will also fly this machine though I was unable to buy one and so went for the 90 which is actually slightly lighter.
Sorry about the monster photo. I thought I had scaled it to a more sensible size. Seems the site software freaks with large files like this one. If you click on it you get a more sensible size image.