Malossi RS1 Performance Rear Shock for Piaggio Zip 50 / Vespa LX50 / S 50. Is rear end of your Zip or Vespa feeling a little worse for wear? If every speed bump and pot hole starts to turn into 3 or 4 bounces up and down, chances are your rear shock is worn out. This is extremely common on the Zip and Vespa 50cc models in particular, the seal fails causing the fluid to leak out and very soon the rear shock becomes a pogo stick rather than absorbing the bumps. The Malossi RS1 represents great value, as an adjustable performance rear shock. Different to the YSS shock, the Malossi offers far more adjustability via the threated spring retainer ring at the top of the shock body – which can be adjusted infinitely between its minimum and maximum values. The RS1 is also 35mm longer than the factory shock, offering a wider range absorbing ability particularly on bumpy roads. This is an awesome value upgrade, and it really makes a instantly noticeable difference to the feel of the bike.