MotoGP 06 Codes -

USA Extreme bike
Press , , x2, , , , x2, at the "Game Mode" screen.

Achievements
Complete the following achievements to unlock the indicated number of Xbox Live Gamerscore points:

Challenge Expert (30 points) - 50 Challenges completed.
Challenge Master (60 points) - All Challenges completed.
Extreme Bike Collector (50 points) - Buy all extreme bikes.
GP: Champion (60 points) - Win a Career mode Grand Prix season under the Champion difficulty.
GP: Legend (100 points) - Win a Career mode Grand Prix season under the Legend difficulty.
GP: Professional (30 points) - Win a Career mode Grand Prix season under the Pro difficulty.
Seeded #1 (75 points) - Seed #1 reached.
Seeded #10 (50 points) - Seed #10 reached.
Seeded #25 (30 points) - Seed #25 reached.
Seeded #50 (20 points) - Seed #50 reached.
Seeded #75 (15 points) - Seed #75 reached.
Seeded #90 (10 points) - Seed #90 reached.
Stunt Mode Rider (10 points) - Play a Stunt mode game in multi-player mode.
Extreme Mode Champion (10 points) - Win any Extreme mode championship.
Extreme 1000 - Legend (60 points) - Win a Career mode Extreme 1000 season under the Legend difficulty.
Extreme 1200 - Champion (50 points) - Win a Career mode Extreme 1200 season under the Champion difficulty.
Extreme 1200 - Legend (75 points) - Win a Career mode Extreme 1200 season under the Legend difficulty.
Extreme 1200 - Professional (25 points) - Win a Career mode Extreme 1200 season under the Pro difficulty.
Extreme 600 - Legend (30 points) - Win a Career mode Extreme 600 season under the Legend difficulty.
Accredited (100 points) - All rider credits awarded.
GP: Rookie (10 points) - Win a Career mode Grand Prix season under the Rookie difficulty.
Finish 50 races (20 points) - Finish 50 races (Xbox Live or offline).
Finish 100 races (30 points) - Finish 100 races (Xbox Live or offline).
Finish 250 races (30 points) - Finish 250 races (Xbox Live or offline).
Finish 500 races (50 points) - Finish 500 races (Xbox Live or offline).

50th Anniversary bike (yellow/white with black bar stripe)
Set your season to 2005 under the "Season" option. Then, win a quick race with Valentino Rossi at Laguna Seca.

Quick Race Extreme mode and tracks
As Valentino Rossi, win Quick Race in GP mode.