Abstract: An adapter (30) for a motorcycle frame (10) configured with a vertical suspension system, as in Harley-Davidson® Sportster®, Dyna®, FXR™ and Road King™ style motorcycles that widens the shock (16) upper attachment points in order to permit the installation of a wider rear wheel. The adapter (30) is configured to attach at the original shock frame attachment point, secured in place by a replacement shock attachment bolt (18?) that is longer than the original shock bolt (18). The structure of adapter (30) provides support against the increased torque of weight on the shock (16), due to the additional length of the bolt, and adapter (30) is correspondingly recessed to closely fit over the junction area (J) of the frame's (10) generally horizontal member (12) and riser (14), so as to resist rotational torques that may be applied to fender, selectably mountable on replacement struts (21).

Abstract: The swing arm of the current invention is a retrofit assembly for a motorcycle frame configured as in a Harley-Davidson Softail™ motorcycle, allowing for the installation of a wide rear wheel, having a replacement swing arm assembly 10 that mounts to the outside 42 of a stock frame 20. The replacement swing arm assembly 10 has two swing arms 12 positioned in parallel and joined at one end by a spanning bar 14 attached to each swing arm 12 a distance below frame pivot bolt 24. The other end of each swing arm 12 attaches to an axle 34 on opposites side of a tire 30. Existing horizontal shock 17 system attaches to the swing arm assembly 10 through spanning bar 14. The swing arm assembly 10 installs with minor modifications to a stock frame 20. Additional room for the tire 30 and its operation is achieved by moving attachment of the swing arm assembly 10 outside 42 the frame 20.

Abstract: A motorcycle modification kit, primarily for Harley Davidson frames, having an oversized wide swing arm for pivotal mounting to a motorcycle frame for supporting a rear wheel having a wide series rear tire. The invention uses offset spacers for the transmission pulley and brake rotor such that the tire remains aligned along the center line of the motorcycle.