supercap:
Heres some more info:
speed (noload)=24000
speed (load) =180001.98 is max current w/load. Part # 273-256.
So I should use gears? What would you recommend? Is there a gear kit??
1.98 amps - definitely won't get that out of a 9V battery for long!
Gears would be ideal, but unless you have some mechanical fabrication skills (or even if you do!) it won't be a cakewalk to design and build a gearbox, due to the tolerances needed so that the geartrain doesn't bind or generate excess friction. This is why I was recommending using pulleys and rubberbands or similar; much more forgiving of misalignment and errors.
Honestly, the best kits to get for small robotics use are the Tamiya gearboxes (see http://www.tamiya.com/english/products/list/educational/kit70001.htm); most can be found or ordered thru well-stocked hobby shops.
If you wanted to try your hand at designing your own gearbox, you might pick up something like:
I think Tamiya also sells a gear assortment (?). Just make sure you buy two sets (one for each motor/wheel).
The only advice I could give for homebrewing a gearbox would be to layout the gears and shafts using cardboard templates and toothpicks or similar for the shafts; then transfer the design to metal or plastic and drill through both sides of the gearbox at once (make sure to use a drill press or keep your drill vertical and perpendicular to the material). Use metal or plastic shafting for the end version (play around with stuff here - you might find, for instance, that pieces of coathanger wire are perfect). Superglue or epoxy the glues and shafts together as needed. Add some light lubricant once assembled (petroleum jelly is OK, or if you have it, silicone-based SuperLube is nice).
Good luck!
