Yamaha XV750 / 920 MZ456-385TRL-06-85 YSS Topline ShocksThese Yamaha YSS suspension replacement shock absorbers from the Topline range, are high efficiency gas shock absorbers that can be adjusted according to the user. There are four main features of this shock: 1. It has a threaded preload adjuster, which the user can turn to personalize their setting. 2. The shock is also rebound adjustable to control the recovery of the shock absorber to its original position, fast or slow, depending on the rider's