Ultra Motor of the UK was founded in 2003 but has now filed for administration.
Ultra Motor produced e-bikes under the A2B brand and also produced e-bike propulsion systems for other companies.
The electric bike company's website said it was "one of few in the electric two-wheeler industry with its own motor production and R&D facilities in Taiwan."
The company also had offshoots in Berlin and sales and marketing offices in North America and Europe.
Ultra Motor has sold its subsidiary Ultra Motor Taiwan to a group of European private equity investors. Ultra Motor Taiwan is the company's propulsion systems business which includes the electric motor manufacturing plant located in Taoyuan, Taiwan, as well as the power electronics R&D facility in Taipei. As part of the acquisition, Ultra Motor Taiwan has received additional funding to finance its growth and continued R&D activities.
Bernd Becker, CEO of Ultra Motor Taiwan said: “We are excited to become a stand-alone company and single-mindedly focus all our resources on the continued growth of our successful motors and propulsion systems business. Over the past 12 months, we have expanded our customer base for e-bike motors and propulsions systems worldwide and we are delighted to receive strong financial support for our further growth."
The administrators of Ultra Motor in the UK are Ensors Chartered Accountants.
Ensors is seeking to sell the company as a going concern. Ultra Motor has a staff of ten in the UK.
The e-bike version of the Brompton, due to be released soon, is powered by an motor developed jointly by Brompton and Ultra Motor.
Brompton marketing director Emerson Roberts said there will be no impact on production of Brompton's e-bike:
"The [UK] bike business has gone into [administration] but this does not affect the R&D arm of Ultra Motor, which is a separate business."