Longboard Bushing Preloader
For our junior design project, my team and I designed a longboard bushing preloader that replaces the nut on the kingpin of any standard longboard truck. My original project proposal had a very specific solution in mind (see proposal here), but our design process led us in a completely different direction. The bushing preloader was a pleasant surprise that came from a great team that responded to the research rather than charging ahead with a championed idea. Once installed it enables to rider to change the preloaded compression of the bushing to three different settings. The set-up as tested was set for optimal riding at 15-25, 25-35, and 35-45 MPH.
CNC Machined tracks
The preloader consists of two CNC machined stainless steel disks and three bearings. The bottom disk containing the bearings is installed against the bushing and the top disk is threaded on with a bit of thread-locker and torqued to user preference with bearings seated in the deepest pocket. The thread-locker must cure before use to prevent the top disk from drifting as the preloader is adjusted.
Simple setting changes
To change between settings, an allen key is inserted into 1 of 3 holes in the bottom disk to rotate it with respect to the stationary top disk until it clicks into the next setting. As the two disks separate, the bushings are compressed further. Increased bushing compression improves stability while sacrificing maneuverability. The preloader eliminates the need for the rider to carry a bulky and heavy tool while providing versatility for various riding conditions. It also insures that the rider can equalize the compression of the bushings for each trucks without counting turns.
Packaging
Though the preloader was never brought to market, we designed some premium packaging that included installation instructions.
If you want to know more about our design process, and how we deviated from the original proposal click "Learn More" to view our comprehensive report.