[remulasce]

A little late now for quick repairs, but check how much the roller mountings weigh in picture 19. That piece holding the bearing onto the frame looks ridiculously overpowered, and way too heavy if it's anything but aluminum. As stated elsewhere, you have a lot of huge expanses of metal plate doing not much of anything. If you can replace the serial cable connecting the sidecar to the CRIO with a ribbon cable, that would be an easy shave of a few ounces. As said, you don't need that thick of chain powering your intake.