 His experiences with Vanwall showed Chapman that his own Lotus 12 design could itself provide the basis for a Formula One competitor.The 12's spaceframe chassis design was adapted to accept its engine in a distinctly offset position and allowed the drive shaft (driven at the engine speed) to pass to the left side of the driver, rather than beneath him, to reach the transaxle located in the rear, lowering the driving position and reducing the frontal area.The drive shaft used Hooke joints (not constant-velocity joints), which at the higher-than-usual shaft angles used produced a vibration at twice engine speed (two cycles per revolution).