Aquiles Guerrero was born on a coffee farm in Nicaragua, was a barista by twelve and a roaster by eighteen. His coffee career in San Francisco began in the late 1980s at his family's shop, Martha and Bros. Coffee. The Stanyan Street roastery was hand-built, mostly from reclaimed wood.
Flywheel took over the Golden Gate Park kiosk in 2020 and opened a branch at 22 Battery Street in 2024. In October 2026 its web shop lists Flyblend, an espresso blend developed for the shop.