REAR SHOCK ABSORBERS BITUBO HD034WMB03 HARLEY DAVIDSON FXDBP DYNA 103 STREET BOB 2013 > 2017. The linear or progressive springs are chosen according to the vehicle. The big adjustments range grants an excellent use both with the only rider and full loaded. This is the reason why we decided to fit to these big scooters the same kind of suspensions designed for the motorcycles. Do not understimate safety and comfort granted by a quality suspension.