Wind noise?  No! Reduce high-speed front-end lift?  No! The only reason the L bumper was added (in the US only) was to meet US 5 mph bumper regulations, courtesy of the insurance industry and probably Ralph Nader too. Wind noise? No! Reduce high-speed front-end lift? No! The only reason the L bumper was added (in the US only) was to meet US 5 mph bumper regulations, courtesy of the insurance industry and probably Ralph Nader too.