We used small steel washers between wheels and the body to help reduce friction and keep the wheels away from the body. We did not use any kind of sleeve on the axle to reduce friction, but we should have. The next year, we put a small piece of a drinking straw around the axle and that worked pretty good as a bearing. Everyone needs to realize that this video was only to show how we made the mousetrap car reverse. It really needed a lot more work to make it work well. So, to ask questions about anything except the reversing part, is really wasting time. We don’t have those answers.