Regarding the crankset, that appears to be a Houdaille Exo Powercam, which was popular with some cyclists as an aftermarket replacement in the mid-1980s, after Lon Haldemann used one to win the 1982 RAMM (Race Across AMerica). If so, the oblong piece is a cam that alters the mechanical advantage and slowed the leg speed through the top and bottom of the stokes, while increasing it through the power section of the stroke.

Edit: Haldemann used the Powercam to win the 1984 edition of RAAM, not 1982.