As you probably know, the OEM linkage on the Gen4 zx10 is not well-suited for track riding, as it is more designed for bumpy streets and 2-up rides. At the track, it means that you will give up rear grip and confidence on corner exits. For this reason Kyle Racing has developed a new race linkage to behave in a linear fashion and increase rear grip of the bike. Be it street or track, the linkage will help your rear suspension behave like a race bike. You can read up on it here: http://www.shop.kyleusa.com/Kyle-USA...-2012-0107.htm $150