Idaten Jump

Sho Yamato is a boy who enjoys MTB a lot. He and his friends Kakeru and Makoto, always practices at the "X-Zone", a place which his father Takeshi Yamato made for MTB, while riding on a bike his father had built called "Flame Kaiser".

One day, Sho is challenged to a race by a MTB group Team Shark Tooth headed by his classmate and rival Gabu Samejima, and whoever wins the race will get the X-Zone. For Sho, the X-Zone had always been a place of happy memories. He has spent many days with his father, who disappeared, so he accepts the game in order to save X-Zone. During the race with Gabu, a black smoke suddenly covers the ground around them, and are sent to another world which is also called as "X-Zone".

When Sho wakes up, he finds Kakeru, Makoto, and his MTB Flame Kaiser are also present. While they are wondering what has happened, MTB riders arrive and challenges Sho to an Idaten battle, a form of MTB race in the X-Zone. They tells that the only way for Sho to return home is by collecting 10 gold emblems by winning Idaten battles while making their way to X-City which is at the epicenter of the X-Zone. This is how Sho comes down to compete in Idaten Battles at various courses such as ghost towns, volcanoes, ancient ruins, deserts, and snow-topped mountains. Now Sho must Idaten Battle for the sake of returning home.

Before an Idaten Battle begins, the MTB riders will put on their bike helmets while quoting "Ready, set, and go". When their bike helmets are on, a full mountain biking suit appears on them during the Idaten Battles. Sho's group decides to head towards the X-City, the main city of X-Zone so that they can get the 10 gold emblem and can return to their home. They also face off against Team Shark Tooth and their various allies even when he arrives in X-City where Gabu is actually the dictator. After defeating Gabu, the black smoke takes them back to earth, but Makoto's brother Kyoichi Shido remains there.

They find that only a half day has gone after staying 3 months in X-Zone. However, they return to X-Zone due to various circumstances, and also find that Imperial X, the bike which controls the energy levels of X-Zone is stolen by mysterious Team X, who controls people by defeating other racers and planting Team X emblem on their bikes. Sho also learns that Takeshi, who is actually alive, is a member of the X-Zone. They also learn that Kyoichi is also defeated by Team X and has become their leader. Sho later defeats Kyoichi in the race and makes him normal, but later learns that Takeshi is the leader of Team X and was the one who stole Imperial X; had been controlling Kyoichi earlier.

It is revealed that Takeshi actually created the MTB bikes in order to save the world from the destruction caused by the activities of an ancient devil who wants to take revenge. An engaging battle ensues, where Sho defeats Takeshi in a MTB battle and makes him normal. Sho stays back in X-Zone as it is his homeland, while the gang, along with Kyoichi emotionally return to earth. Few days later while the gang are practicing, they reminisce about Sho. To their shock and happiness, Sho returns to earth telling that Takeshi has sent him to be with his friends.

• Official website
• Idaten Jump (manga) at Anime News Network's encyclopedia