"Yowamushi Pedal: Spare Bike" is a continuation of the "Yowamushi Pedal" series, focusing on the competitive world of high school cycling. The story centers on Sakamichi Onoda, a first-year student at Sohoku High School who initially joins the anime club but discovers a passion for cycling. Despite his lack of experience, Onoda's natural endurance and determination quickly make him a key member of Sohoku's cycling team. The series follows his growth as a cyclist alongside his teammates, including the ambitious Shunsuke Imaizumi and the spirited Naruko Shokichi.

The narrative delves into the Inter-High competition, where Sohoku faces off against rival schools, including the formidable Hakone Academy. The rivalry between Sohoku and Hakone intensifies as both teams strive for victory, with Hakone's ace, Arakita Yasutomo, and their captain, Fukutomi Juichi, posing significant challenges. The series highlights the strategic and physical demands of competitive cycling, emphasizing teamwork, perseverance, and personal growth.

Key arcs include the intense training sessions, the development of individual riding styles, and the psychological battles between riders. Onoda's unique ability to climb steep hills with ease becomes a crucial asset for Sohoku, while his teammates contribute their own strengths to the team's dynamic. The series also explores the backstories of supporting characters, providing depth to their motivations and relationships.

"Yowamushi Pedal: Spare Bike" maintains a strong focus on the camaraderie and rivalry within the cycling community, blending high-stakes races with moments of humor and character development. The narrative builds on the foundation laid by previous seasons, offering a mix of intense competition and personal milestones for the characters.