Originally Posted by MadMac

Ok... here is a little experiment for you...

Get a long sturdy tree branch, jam on end into a vice or something that will prevent you moving it.

Now grab part of the branch closest to the vice and try and snap the branch. Now depending on how strong you are or arn't you may break it. But its probably going to be hard work doing so.

Now grab the end furthest away from the vice and try and break it. You should find holding the far end means its easier to break it.

Now imagine the vice is a wheel hub and bearing, the branch is a spacer and your hand is the wheel. By placing a spacer between the wheel and bearing you are creating the same effect. Your moving the wheel further away from the point where the load is transfered along the suspension. Ideally you want all support directly over or under the place where the load is applied not 140mm out to the side of it.