My mans on Fire !...........Great info John.......Any bearing house will have them. They have numbers on them. I replace all my bearings with german bearings. You want at least ABEC.5 rated bearings. The higher the ABEC rating the easier the bearing rolls. Do a google search on where to buy them in your area. While youre at it you should make sure to chain is aligned straight,brakes,ect. Its amazing how much speed you gain by making sure everything is straight,and has less rolling resistance.
Great place..........I get all my r/c bearings from there........I get all my bearings from vxb.com