Bradford Council has been accused of “crass naivety” if it thinks closing a layby will stop the unofficial use of an off-road biking site.

City Hall has been challenged by a motorcycle governing body to think again about closing Flappit, near Cullingworth, which has been used by trials riders for 50 years.

Council officers say they must put the disused quarry workings at Hallas Rough out of bounds on health and safety grounds and are to close the layby, which gives access to the site, in the next few weeks.

A 45-year-old quad bike rider from Micklethwaite died at the site in April 2007 when he lost control of his machine.

Dave Luscombe, senior officer of the Auto-Cycle Union, said the closure would not stop bikers finding ways on to the old quarry workings.

And he believes off-road riders are being discriminated against in comparison with people in sports like cricket and football which are supported by the local authority.

He said: “It is crass naivety to think closing the layby will be the answer.

“It will now become a free for all as people try and get on the site from other places on machines that are designed to deal with obstacles.

“What is annoying is that people who play tennis, football and cricket are catered for by the local authority but motorcyclists like this are not.

“And it is sad that an area which has nurtured such great riders as 12-time world champion Dougie Lampkin and has people who want to follow in his footsteps, is being discriminated against.”

Other local authorities in the country had been successful in helping to set up similar sites despite complex legal issues, he added.

Cllr Margaret Eaton (Con, Bingley Rural), who is chairman of the Local Government Association, said motorcyclists had a genuine right to pursue their interests but somewhere safe and where it would not interfere with local people.

Flappit was not the right place because of the health and safety issues, she added.

She said: “I have never had as busy a post bag in the last two or three years as on this issue, which is about health and safety. We have no option but to deal with them. I don’t want to deprive people of their enjoyment. This is not about who is right and who is wrong. It’s a very complex set of circumstances relating to the legality of using common land.”

Users of the common land site held a mass rally when more than 100 people turned up to oppose the layby closure.

Bradford Council made its decision to close the layby before Christmas and is now looking to enact the order within the next couple of months. Double yellow lines have already been placed along the A629 Keighley to Denholme road near the entrance to the layby to prevent parking.