Convoys of go-karts evoking the hit Nintendo Co. Mario Kart series have become a head-turning sight among Tokyo's traffic, but the rental companies behind the vehicles, with a customer base comprised mostly of foreign tourists, face growing scrutiny over safety concerns.Rental operators let customers drive often-crowded public roads in the low-slung vehicles while dressed as characters including those from the popular racing video games from the Mario franchise.Despite the legality of the operations, the Japanese government has raised concerns over the lack of safety measures being taken by…READ FULL ARTICLE