RE: Webra ID
Exactly, that's it!
The Racing 61F C, as you can find it on the Webra home page (aero engines) is the revival of the "classic" Webra Racing (1030). It has a modified crankshaft (8mm instead of the former 1/4"). Bore is still 24mm, stroke 20mm, recommended propellers 11x6/12x8, everything typical for a SHORT stroke.
Rainer