Four fire engines and around 25 firefighters were called to a fire at a workshop on Acton Street in St Pancras.
Part of a lower ground floor electrical bike workshop and the mezzanine floor of a four-storey building were damaged in the blaze. Several electric bikes were also damaged. There were no reports of any injuries.
Firefighters also removed two CO2 cylinders from the scene as some cylinders can explode when exposed to heat.
The Brigade was called at 0449 and the fire was under control by 0546. Fire crews from Euston, Islington and Soho fire stations attended the scene.
The cause of the fire is under investigation.