Here are the links for the two parts I recently used for a Keda 38mm 2800KV Inrunner ( 1800 watts! )

The gear drive mates perfectly with the mount... You just buy the appropriately sized gear drive and mount.

The drive comes with a couple of pinion gears so you can vary the reduction amount.



[link=http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXMLK0]Gear Drive - Click me![/link]

[link=http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXLCL5]Mount - Click me![/link]

For something like the above motor, you would want to use the "medium" (28mm) or small, gear drive and mount, then select an appropriate reduction depending upon the voltage.

e.g. if using 11.1v a 3:1 would be fine.