The gameplay of Rad Racer II is virtually identical to that of its predecessor: the idea of the game is to race around a course, and make it to check points before the car's fuel (game timer) runs out. If the player hits another vehicle, road sign or tree at a high speed, the car crashes. Crashes take time and make it more difficult for the player to reach the check point. To help prepare for high-speed turns, the dashboard has a preview direction indicator, an arrow that indicates which direction the track will take in the next few moments, allowing the player to position the vehicle accordingly. Also, the new ability in this version of the "Turbo Boost" is performed by holding the down arrow when the race begins until the audio countdown stops. Of course, this requires some practice, but it is quite useful.
Source: Wikipedia, "Rad Racer II", available under the CC-BY-SA License.