The innovative and self levelling centre pivot assembly is based on 3 instead of 4 joints. From this result outstanding driving and direction characteristics. This unique Hamm pivoted steering with the 3 ball joints guarantees an unsurpassed directional stability and driving comfort. Even with full steering angle the chassis construction provides for an even weight distribution on drum and wheels and ensures in such a way for careful absorption also with uneven terrains. Tilting with driving along curves is also more strongly avoided.