About Us
Who we are
Who we are
Kosei Garage is a weekend motorcycle workshop,
working to eventually serve the motorcycle community in the SF Bay Area.
The name Kosei comes from the Japanese words 個性 (character) and 恒星 (star),
showing our passion for brightening up the character of every machine we work on.
The Team
The Team
June / Jumpei Yamaguchi
June / Jumpei Yamaguchi
June dedicates a lot of his time to supporting the motorcycling community around him with passion and dedication to his work.
Our History
Our History
Our origin is from the founder June reviving his friend's crashed R6 in the fall of 2024.
We've been serving many riders and motorcycles since with services, diag, and repairs.
Kosei Garage was started as a project in January of 2025, hoping to serve the bigger community of riders.