Rockstar finally added the Shotaro to GTA Online two days ago, alongside a new outfit and Adversary Mode. All three new additions were greatly inspired by Tron, one of the most iconic sci-fi movies of the 80's. The outfit became an instant hit due to it's unique Sci-Fi design, however fans begrieved the fact that the various elements could not be mixed and matched with other outfits — until now.

A bit about the update itself, first. The new Adversary Mode, titled Deadline, is basically just Tron's light-cycle battles adapted to GTA Online's mechanics. The only major difference is that instead of the energy-trails forming endless walls, their length is limited, and rather become "tails" that follow the player's Shotaro.
Playing the new Mode is required to unlock the Shotaro for purchase at Legendary Motorsports, and the bike costs a whopping $2,225,000, making it the most expensive bike in the game by far. However, some might argue that it's worth it, since it's also the fastest and has great handling.