Infinite fuel (Japanese version)
Pause the game and press Up, Down, Left, Right.

Birdman star locations
Finding a Birdman star will allow access to the Birdman suit. The screen will turn white after the star is obtained. Note: The Rocket Belt is required to reach all of these locations except for Holiday Island.

Holiday Island: Under the natural arch on the beach.
Cresent Island: In the hidden cove on the beach located between the airport and little village.
Little States Island: Center of Central Park in New York.
Ever-Frost Island: Deep inside the cave that feeds the smaller waterfall. Go to the end of the cave and change the viewpoint to look downward.
Refueling locations
There are two gas stations on Little States Island. Follow the road to the northwest from Cape Canaveral in Florida to find a gas station on the left with a sign displaying the Paradigm logo. Get near to the ground and approach it until the sound heard during take off from a hopping pad is heard. The other gas station is in the small town near the nuclear power plant in the Midwest. Fly into that town with the Rocket Belt or Gyrocopter to get under the little gas station roof.

Hints
New York to San Francisco warp
Enter the green office building near the start in New York. Then, a Nintendo 64 logo will be inside the building. Fly through the building and exit in San Francisco. Now the trip may be reversed if desired.

Miami to Seattle warp
Fly inside the space shuttle hanger in Florida, fly towards the ceiling, then turn around and fly back out to emerge in Seattle. Now the trip may be reversed if desired.

Wario on Mt. Rushmore
Hit Mario's nose on Mt. Rushmore with Gyrocopter missiles or a cannonball shot. Then, his face will transform into Wario's face.

Driving the Gyrocopter
The Gyrocopter can be driven on the ground by landing anywhere after getting enough forward momentum in the air.. After landing, keep moving forward. Note that the Gyrocopter will become airborne again if its speed exceeds 40.

Rocket Belt, Pilot Class shortcut
There is a shortcut in the cave on Crescent Island. There is a left turn that leads down a straight section after the first stalactite in the cave. The cave narrows midway through the straight section,. Just after the narrow section is a torch on the wall. Turn right at the torch to reach a branch in the cave. Avoid touching the wall in the very narrow sections.

Night time on Rocket Belt, Beginner Class
Enter the cave in front of the chapel on top of the hill. There should be water coming out of cave and a sewer grate deep inside. Fly to the sewer grate and the game will slow as a strange noise is heard. The cave will turn darker. Exit the cave to fly outside at night.