with suspension arm? axis: 20mm, ? steering tube: 36mm, steering lock: half moonProduct descriptionSteering column for Vespa PX models with a stand tube shortened by 20mm. With the Serie Pro steering column shortened by 20mm, Vespa Px models can be lowered at the front. 20mm shortened For original PX Ideal for lowering the scooter How high or how low a Vespa is at the front is not determined by the length of the fork, but by the length of the shock absorber installed. However, if only a shorter shock absorber is installed, the swing arm angle and the caster will change. Under certain circumstances, the swing arm may hit the fork when it is compressed. Therefore we offer shortened steering columns. The column shortened by 20mm is only very moderately modified. It is therefore suitable for slightly shortened PX shock absorbers or at most for PK shock absorbers in original length. However, the swing arm angle changes. How long the shock absorber should exactly be in relation to the fork