GWS P-51 gear ratio
 

Does anybody know what the gear ratio is on the EPS-300C gearbox that ships with the P-51? I notice that there are several different gear ratio replacement motors that you can get for this plane, but I can't find what the original ratio is.

Thanks,
Duncan

GWS P-51 gear ratio
 

Look at the spur gear (the big one). There should be a letter embossed on the face of the gear. That's the ratio of the gearbox. You can look it up at http://www.gws.com.tw

If all else fails, count the number of teeth on the pinion (little gear) and the spur, then divide the spur number by the pinion number.