AGGRESSIVE mountain bikers are frightening visitors to an historic country estate by hurtling along bridle paths at breakneck speeds, warns the chairman of its Friends group.

St Ives Estate, near Bingley, is a magnet for cyclists who ride at speeds of up to 32mph said Pam Laking, whose call for their behaviour to be curbed is echoed by ward councillor Simon Cooke.

He has asked Bradford Council to tackle the issue and officers now are drawing up warning posters to deter anti-social cycling.

Mrs Laking said last month two horse riders on Blind Lane were first scared, and then harangued, by a gang of four bikers.

"They came silently whizzing down hill and so fast they nearly hit the horse riders, who they then abused, even saying, 'If you don't get out of the way we'll ram the horses'," said Mrs Laking.

"One of our committee members has been nearly knocked over and there are many other examples.

"I'm sure a lot are nice, but the majority of all complaints Friends of St Ives receives are about cyclists.

"One of the problems is the bikes have no registration numbers, the riders are all just lycra and helmets, so there's no way of identifying them."

She said some of the cyclists were difficult to deal with.

"They tend to be so aggressive and unpleasant - it's not about enjoying riding a bike in the countryside or appreciating nature, it's just about competing against themselves to go faster and harder on difficult terrain.

"Times and speeds are then logged on internet sites and I saw one where someone had clocked 32mph going down Blind Lane.

"Those times are posted as challenges for others to beat and there are routes with names such as the Hard End Bash, which goes over Harden Moor and St Ives.

"We also have a major problem with gangs of up to 30 going up in the dark and using headlamps to tear all over the estate doing a lot of damage when no-one's about to stop them.

"It's very worrying."

Councillor Simon Cooke, (Con, Bingley Rural) asked a full meeting of Bradford Council what was being done to reduce the "speeding and appalling behaviour" of some cyclists at St Ives.

He believes there may be an over-zealous attitude towards promoting cycling.

"I do fear that as an organisation the Council has become a bit bicycle obsessed," Cllr Cooke said.

"The view of the general public is that some mountain bikers have got far too big for their boots and we need to manage interaction between them and other users of places like St Ives," he said.

A Bradford Council spokesman said: "We are designing signs to be put up in St Ives Estate to encourage cyclists to share with care. We want as many people as possible to enjoy our beautiful outdoor spaces and we want everyone to use the area safely."