How to attach hex wheels to gear motors?

[carp]

Hi Jw, dont think it will be possible to drill into the hex on these rims, i think that the idea you said about drilling the motor shaft and putting a pin through maybe the best option, i did a bit more searching last night and found these http://compare.ebay.co.uk/like/18091...var=sbar&cbt=y

pin will go through a hole drilled on motor shaft then the grub screw holds it all on, tire goes over it then a nut threads on and holds tire in place this video shows how they would fit on http://www.youtube.com/watch?v=iyK7mmlU-Oc

Already have the wheels they are 14cm diameter for 14mm hexes and 18cm diameter for 17mm hex, dont have any gear motors for these yet still unsure on how much power it will need to move it about.

thanks