I previously added a bearing to each of my front carriers:
http://www.rc-monster.com/forum/show...t=26979&page=8
Now I'm getting around to doing the same to the rears. I used an 18mm OD Al tube, 1mm thick, as a sleeve for another 16mm bearing:
So that I can go from this:
to this:
With sleeve and extra bearing installed:
I did this to help give more support to the axle, since the thin 15x21 bearings have failed at least once on me previously.