Boris Johnson's promised "Cycling Revolution" for London appears to have been consigned to the ancient history the city's mayor is so fond of quoting, replaced instead by what is termed a "step change" for cycling in the city - but with some projects running years behind schedule and concerns over cost, will the mayor's vision be fully realised?

It may seem no more than a question of semantics, but the use of a different phrase, highlighted in a document published last month, may in part reflect that the changes to facilities for cyclists in the capital demanded by campaigners cannot happen overnight.

Now, the fear will be that some of the changes the mayor has promised to encourage cycling and make conditions safer for people on bikes won't happen at all, or that financial pressures will cause some to be dropped.

Previously, the London Plan, published in July 2011, stated succinctly:

The Mayor is committed to seeing a revolution in cycling in London.

But in the Draft Further Amendments to the London Plan, open for consultation until 10 April 2014, that is replaced by the rather more expansive:

The Mayor is committed to delivering a step change in cycling provision that will support the growing numbers of cyclists in central London as well as encourage growth in cycling across all of London. The Mayor's aim to increase the mode share for cycling to 5% across Greater London will require significant increases in particular areas and for particular trip purposes - e.g., Central, Inner and mini-Hollands, leisure trips across the capital and commuting trips to London.

The proposed amendments suggest that some promised initiatives may not happen in the way envisaged when they were first launched - for a start, former references to 12 Cycle Superhighways have been dropped, and the project is running well behind its original timetable.

The first two routes - CS3 from Barking to Tower Gateway, and CS7 from Merton to the City, were launched amid much fanfare in June 2010, with Mr Johnson promising that they would encourage "legions of Londoners" to take to their bikes - although from the outset, some derided them as being little more than a lick of blue paint.

The rollout of the Cycle Superhighways, originally due to have been completed by the end of 2015, was put on hold following several cyclist fatalities in late 2011, including that of Brian Dorling at Bow Roundabout, the first rider to die on one of Mr Johnson's flagship routes.

Now, the timeframe is that the routes won't be completed until some time between 2017 and 2021/22, and the commitment to build a dozen of them has disappeared. Moreover, according to new text inserted in the draft of the London Plan, they are "under review and subject to change."

In part, the deferral of the anticipated completion dates reflects the fact that other initiatives announced more recently have been given greater priority, including the two planned segregated routes running across the city centre and the trial of Mini Hollands in up to four boroughs, both due for completion by the end of 2016.

The reference to four boroughs is a change from the original proposal, which envisaged between one and three being chosen from those that applied, but again the timetable is slipping - the identity of the successful boroughs was due to have been revealed by the end of 2013, but there's still no news.

The delay to the Cycle Superhighways also results from the fact that in December 2011, Mr Johnson ordered a review of all junctions on the existing and proposed routes. That was subsequently expanded to some 500 junctions throughout the capital.

Last year, in his Vision for Cycling in London, Mr Johnson announced that 100 had been identified for improvement under the Better Junctions programme.

But that has subsequently been scaled back, too - in December we reported that the number of junctions that will be improved has been cut to 33, and 15 of those are part of separate projects such as Cycle Superhighways.

The website Transport Xtra reports that Leon Daniels, TfL's director of surface transport, told the its board: “The current scope of the programme is still being finalised, including the number of cycle superhighways and the extent of interventions."

However, he added that the experience from the additional safety features introduced on the CS2 Stratford extension pointed towards more money being needed than was originally budgeted.

“This indicates that the overall costs for the programme are likely to increase by up to £50m to ensure adequate service standards are provided on all routes,” he explained.

Mr Daniels added that a choice would need to be made between reducing the number or length of the Cycle Superhighways, or to take money from other parts of TfL's cycling budget.

That already faces a shortfall after Barclays announced in December that it was ending its sponsorship of the Cycle Hire Scheme and Cycle Superhighways in 2015.

The news came as a surprise, with Mr Johnson having announced in 2011 that Barclays had agreed to extend its sponsorship until 2018.

As a result, it appears Barclays will end up paying less than half of the £50 million it had been expected to contribute.

When the decision to end the deal was revealed, Graeme Craig, TfL's director of commercial development, said it planned in future for the Cycle Hire Scheme sponsorship to "become part of a much wider and larger cycle sponsorship offer."

He said that would include elements of the Mayor's Cycling Vision such as Quietways and the proposed east-west and north-south routes cutting across the city centre.

The latest draft London Plan also deletes an earlier undertaking to "identify potential sites for expansion and/or standalone schemes in outer London."

Mr Johnson has pledged to spend £913 million on cycling in London between 2012/13 and 2021/22.

We will looking in detail in the coming days at some of the aspects of cycling in the capital contained in the Draft Further Alterations to the London Plan.

In the meantime ere is a summary, taken from the same document, of the schemes currently planned and their anticipated completion dates.

The amounts shown next to each reflect how that £913 million is currently allocated, according to Mr Daniels' report to TfL's board.