Sugimoto Sadatoki is a new first-year student at Sohoku High School who later joins the Sohoku High Bicycle Club. He is the younger brother of Sugimoto Terufumi. His cycling style is very similar to his brother's.
Appearance
Sadatoki's appearance, unlike his cycling, is vastly different from his brother's. He has very short hair and thick eyebrows. He is also very tall, loud, and strong. His strength is exemplified during his introduction when he breaks the door to the clubroom and later picks up two bikes, one in each hand.
Personality
Sadatoki is an immensely sweet person and younger sibling. While most people on the team might not know what to think at first, due to Sadatoki's very overwhelming volume, size and strength, his kindness and respect for others is quickly evident.
He often mixes up phrases and when to use them, for instance, saying "Thank you for the food!" rather than "Excuse my intrusion!" when entering the club room for the first time. His exuberance can overwhelm his own common sense, but much like Onoda, he does his best to make up for any situation.
Plot
Sadatoki is introduced before he enters Sohoku High, invited by his brother to visit the club room in the fall after the first Inter High. While the team is confused at first, Sugimoto insists and shows off his younger sibling's strength, loud voice and skill. In the anime though, he was shown to had ripped the door clean off the hinges as it was locked.
In the anime, Imaizumi questioned his balance and dexterity, hence testing him to ride on rollers before joining them in practice, which Sadatoki passed with ease, even when he had never been on one before.
While Sadatoki seems unskilled in actually racing at first, it is shown that he is more than it appears to the eye.
He later aids Sugimoto in a race. While he does not make the Interhigh team in his first year or finish the 1000 Km training camp, he does do better than his older brother did before him and he also beat him in terms of time when his older brother retried in his second year and impresses the older members of the team. He finished first out of all that didn't finish the 1000km (191 laps)
Skills and Techniques
While he lacks stamina, Sadatoki has a talent for copying and emulating other people's cycling styles, especially Terufumi. He seems to be unaware of this feat and only capable of copying someone if he likes them enough to get a hold of their style, but it reveals a talent for cycling that may well become a real force in the future. He became aware of the feat when Teshima told Imaizumi to drop back and order Sadatoki to copy Onoda's form. Sadatoki did exactly that, but his poor stamina took its toll on him. During training camp, he rides at a seemingly leisurely pace on his own compared to Kaburagi Issa.
Relationships
Sugimoto Terufumi
Sadatoki has a great deal of respect for his older brother Terufumi. He thinks that Terufumi is cool no matter what he does.
Onoda Sakamichi
Sadatoki said that he heard stories of Onoda from his older brother, so he was looking forward to meeting him. He was not discouraged by Onoda's small stature, saying that he is "small but strong." Sadatoki admires Onoda and calls him "Onoda-san," much to Onoda's excitement and embarrassment.
Trivia
Likes: Rice Balls
Favourite phrase: "Thanks for the food!", even when expressing gratitude to someone.
The Kanji for his first name means "To be punctual".