The BMX Sidehack, aka sidecar. These mutants were birthed during the Old School Era of BMX, they largely disappeared except for some isolated cultural pockets in southern California and strangely sports clubs in Europe…kinda like the mullet haircut.
During the old school era, the start ramps may not have been as towering as today’s elite concrete BMX stadium tracks, but overall the dirt tracks were typically downhill with less jumps, more favourable for sidehack races. Rather than being a passive passenger, the “monkey” pushes against a bar when the sidehack slows and moves his body side to side to keep the sidehack from tipping in the turns.