Whats a good starting prop for a 50cc Gasser( Quadra 50 EI)? I have a 20 x 8 Zinger Pro. Is it enough prop?

Turbo

20 x 8 seems too small. You want your rpm around 6700 - 7000 at full throttle. A good break-in prop for a 50cc is 22 x 8. After break-in go to a 23 x 8. Everyone has their own preference, I like Mejzlik CF

When in doubt, use a tach to double check the rpm as stated above. My smaller 39cc gasser already spins a 20x10, so you do not want to use a 20x8 on yours.

I used a Menz 22x8 to break in mine and then a NX 23x8,,, also has a 22x10 BME it looks really cool but it's too big for it!!!!

Thanks for the info. I'll start with a 22 x 8 or a 20 x 10.

Regards,
turbo

They are not exactly common, but there are some 21x8 props made. Since we lose some power at our 4500 ft. elevation I started with a BME 21x8 on my ZDZ-50 for break in, then to a 22x8 Mejzlik which seems to work really well. I also tried the 22x8 Bambula but it was too much load on the engine.

Which brings up the other thing about prop selection, there are quite a few different profiles out there producing different RPM numbers in the same size when switching between brands. So it really is a trial and error deal that can depend on specific airframe/engine combos and what kind of flying you like to do, which can be kinda spendy...