[Holtzman]

I know exactly what your talking about. I saw number of 6 wheels that suffered from the same problems.

Question: Where you using the KIT Bot chassis in the 6 wheel configuration?

The kit bot chassis was notoriously bad for twisting under turning forces(sorry John). This twisting forces the front and rear corner wheels into the ground, giving you the center and rear wheel on the ground on one side, and the center and front wheel on the ground on the other side. This is what causes the oscillation your talking about. It is only compounded by the fact that you have a large weight up high. Reinforcing the chassis will help to minimize this twisting. A good example of this is 229's robot(Thanks John).

Its also very important that you balance your robot about the center wheel in a 6 wheel drive robot. Not balancing about the center wheel will also contribute to these oscillations.