The kingpin on the Aerolith (Aero Pro’s truck) is designed to accommodate the use of two tall bushings. If the kingpin were mounted the standard way with the threads on the road side, using a standard height bushing on the road side would leave excess threads exposed. Pointing the kingpin inward protects those threads from wear and damage.

The inward orientation also allows for changing bushings without detaching the hanger. This is particularly helpful for the rear truck where the drivetrain can make detachment more cumbersome.