Nextbike claims it landed the contract due to its commitment to a Midlands-wide bike share scheme including Dudley, Sandwell, Walsall and Wolverhampton, with other bidders wanting to run it in Birmingham only.
The German firm had its contract cancelled last Thursday after the West Midlands Combined Authority (WMCA) accused it of "persistently" missing targets.
Nextbike – which says it spent £700,000 on the scheme – was supposed to roll out 5,000 bikes across seven areas, but managed just 25 as part of a pilot project in Wolverhampton.
Bosses insist the firm had overcome a series of challenges, including a worldwide shortage of a key component – RFID readers – and a dearth of sponsors willing to put in the £2.6 million required to run the scheme.
Krysia Solheim, nextbike UK managing director, said: "We have invested more than £700,000 in trying to get the West Midlands scheme up and running.
"We dedicated hundreds of IT development hours to integrate our platform with SWIFT, ordered parts for the first 500 bikes, organised the infrastructure and locations for the stations and were preparing to unveil a key sponsor.
“There have been constant hurdles to overcome and the landscape changed significantly after we won the tender.
"At every step of the process we have kept WMCA informed and worked constructively with them to find solutions. We held up our hands when global supply of the RFID readers dried up, but we were committed to bringing this scheme to the Midlands.
“We won the tender for a variety of reasons, not least because we’re the most extensive bike share operator in the world.
"Other operators in the frame simply did not want to commit to a Midlands-wide scheme, preferring just Birmingham.
"So that’s what’s so disappointing about WMCA’s decision to quit - key territories such as Dudley, Walsall and Wolverhampton would really have benefitted from a scheme such as ours.”
Mr Street, who heads the WMCA, has championed the bike share scheme, seeing it as a key part of his plans to get commuters off the roads and into other forms of transport.
The scheme has seen a slow take up in Wolverhampton, with an average of just seven rides taken per day.
The WMCA says it is committed to finding another supplier to take over the scheme.
Nextbike operates bike share schemes in 200 places around the world, including Cardiff, where it has been blighted by up to 40 cycles a day being vandalised.