Thanks for taking the time. I figured the numbers they assigned were relevant, just wasn't sure how. One would think that one of the most popular companies out there would label their stuff like everyone else so as to avoid confusion.For the 1406 -
The diameter is 14 = 1.4" = 35.5mm
The rotor length (not can length) is 06 =0.6" per castle specs, this motor can is 49.5mm long. So this is a 540 size motor.
For a 1410, same 1.4"=35.5mm can diameter, but the rotor is now 1.0", and the can is 53mm, so a 550 size motor.
For the 1415, same diameter, but the rotor is 1.5", can length is 70mm. So 3670 size
Interesting, though, the 1515 is listed as 75mm long, even though it has the same 1.5" rotor length. 1515 = 4075 size.