stobby
Reverse the wires, and it WILL run the other way
Now there are two possibilities:
1 it runs at the same speed and takes the same no load current as its mate or
2 it behaves differently (it will not be a big difference)
If you find (1) then the motor is neutrally timed, and doesnt care which way it runs - Ahhhh the Cox reed-valve engines
if it is a case of (2) then one of the motors needs to be retimed (You still don't know which one has the correct timing for its rotation)
AFAIK ALL motors can be retimed, even if they are not designed for it and have swaged cases and end plates
I'm not able to give detail on retiming, but there are published procedures which the speed merchants have discovered.
But my (less than perfect) understanding is that "Speed" motors come very nearly neutrally timed, since Graupner can't guess whether you are going to go for direct drive, geabox or belt drive
Also: most "Speed" motors, but not all of them have a built in capacitor between the brushes (you can often see the terminal wire coming out of the case and wrapped roung the terminal tag). This is much better than nowt for radio supression, but it is very sensible to also fit a full supression kit to a high power brushed motor - three (more) capacitors.
Hope this helps a bit
andrew