Ever wonderred what is going on on your RC car or truck every time you try to make it go forward, turn and stop? These types of objects may be small but there are a lot of actions happening at the time you try to make it move. How about what the things that are involved when you want to make your car go faster? What does it take really?
If you want for your RC car to go faster during a race or simply during an afternoon practice, the best and very economic answer to that would be to use shims. What are shims anyway? A shim is a thin metal or a wedge which can also be made of wood. It is placed in between your RC parts to help the RC car maintain its level just in case it goes over rough roads, large stones and the like. An RC car with shims reduces sloppiness while it runs.
The area where you can put a shim is in between the rear hub and axle pin since there is an obvious gap between the two materials. You have to first disassemble the parts starting from the rear hub and then the axle pin. Then, assemble again the rear hub but this time, place the shim next (the shim could be plastic made, wood or metal) followed by the bearing.
Take note that the shim you will be putting should match the same dimension of the ball bearing to ensure that it will work properly. What the shim does is it minimizes the gap in between the axle pin and the bearing. This should do the trick in making your RC car run faster.
There is one downside to shimming though. If there is too much shim, it's possible for the tires of your car to bind. True that it will not slop any longer but binding then is going to be your next problem. So make sure that you do not use too much shim on your bearings.