In 1998 Don Angel crashed the Vincent streamliner. The only injuries were a bruised shoulder and his right leg, which sustained a three inch cut on the shin bone. He reported his legs were thrown around inside the liner, causing his right leg to hit the toe release rod. The leg restraint used prior to the accident was simple, a piece if padded tubing over the top of his legs underneath the canopy. This system prevented his legs from exiting the streamliner, but I saw there was still too much movement of legs, so I redesigned the system.
The leg restraints now employ wrap around velcro straps at the ankles, which affix to steel plates with half inch holes. When the handlebars are lowered there's a mechanically operated pin which goes through the steel plates and secures the ankles from moving up and down, but still allows slight fore and aft movement for brake and throttle operation. When the rider exits and raises the handlebar, the pin is mechanically extracted from the holes, allowing quick exit.
After Leo's incident, I plan to improve the system even further by an additional securing mechanism for raising the handlebars. In the event of a crash where the handlebars would be prematurely released, thereby releasing the leg restraints, wouldn't be a good thing.
Pictures of that 1998 crash are on my website,
www.vincentstreamliner.com.
Max