We have received feedback from customers that the air spring suspension does not work well enough in some circumstances and that the grip between the rear tire and the road surface is too weak. We have thought of making an elastomer suspension. But we want to test this first. That is why we asked Intercitybike if they would be so kind as to lend their rear suspension design. We now place this in the rear suspension of the SL / GT. If you have an MK5/6 with air suspension please contact your dealer for a replacement.