A group representing motorcyclists in the UK has postponed a demonstration planned for a week tomorrow against Mayor of London Boris Johnson’s flagship East-West Cycle Superhighway. The Motorcycle Action Group (MAG) says it has achieved a “major breakthrough” with Westminster City and will be holding discussions with the local authority.

The demonstration was due to have been held in the capital on Saturday 30 May, but the MAG now says it will “sit down with key players in the WCC to promote the benefits of motorcycling and highlight the potential adverse effects of the cycle scheme on traffic movement in the City.”

The organisation, which claims to have around 50,000 members, says it “is sympathetic to the expectations of cyclists as fellow users of single track vehicles," but insists that "the justification for turning over such large areas of road space seems disproportionate and likely to cause severe congestion that will ironically prejudice efforts to enhance London’s air quality.”

It is also campaigning against proposals to charge motorcyclists £12.50 a day to enter the planned ultra low emission zone in London, the same as Transport for London (TfL) intends to charge motorists.

Most of the route of the East-West Cycle Superhighway passes through the City of Westminster, including the stretch along the Embankment west of Temple, and Bayswater Road once it exits Hyde Park.

Separately, The Royal Parks, which is the body responsible for the St James’s Park, Green Park and Hyde Park, all of which the proposed route passes by or through, has blocked plans for it to pass immediately in front of Buckingham Palace and also wants it routed away from Birdcage Walk.

Selinda Lavender, MAG’s chair, said: “While MAG is an activists’ organisation, we don’t use demonstrations gratuitously. The door on discussion has opened somewhat, possibly because of the prospect of a demonstration.

“The demonstration will still go ahead this summer unless major compromises are made both to the Superhighway scheme and the plan to charge motorcyclists the same as motorists to enter central London.”

The MAG’s transport policy and campaigns adviser, Dr Leon Mannings, said in his response to TfL’s consultation to the scheme last year that he objected to the plans for the East-West Cycle Superhighway, as well as the one running from North to South, “in the strongest possible terms.”

Among his criticism was the impact on powered two-wheelers such as mopeds and motorbikes reduction of road space, including the safety of riders, and he expressed concerns that the scheme would lead to more congestion and longer journey times.

Dr Mannings, who is also a member of the Parliamentary Advisory Committee on Transport Safety and the Mayor’s Roads Task Force as well as TfL’s Design Review Group for the Cycle Superhighways and Better Junctions for Cyclists programmes, also said the consultation period was too short.

He added that insufficient consideration had been given to a potential link between cycling and prostate cancer in men as part of the cost-benefit analysis of the scheme, an issue he said he had raised with “senior figures” within TfL.