mi wheels fit on the rc18b no problem. You need to use mi hexes though. You can use plastic or aluminum hexes. You may also want to use a spacer on the axle shaft (outside of the wheel) when you tighten down the axle nut you will notice you have a lot of exposed thread (axle is long) if you leave the exposed thread and crash you may have trouble removing the elastic stop nut.....If you have old or extra nuts they work. I found nylon spacers at Sears Hardware.