Amazon.com: Shock Shock Absorber Type 641 Piggyback Clipart tango face surprise shock YouTube. This high performance rear shock set for Harley Davidson touring models was developed in collaboration with the Harley Davidson Germany Bagger Race Team and fine tuned on the racetrack. The Piggyback Kit perfectly balances sportiness and comfort, offering adjustable rebound and compression damping plus infinitely variable spring preload. As with all Wilbers products, each set is built to your exact specifications and delivered with ABE and a 5 year warranty.