Unmarked police motorbikes are patrolling key routes in a bid to cut biker deaths.

Signs are being put up warning bikers about the patrols to try to discourage speeding and anti-social driving.

The move came as police revealed two men were arrested for allegedly reaching speeds of up to 125mph on motorcycles on the A27 on Sunday.

Signs are being erected on routes including the A272 in West Sussex and the A22 in East Sussex.

The first was unveiled at The Pike, Washington, near Storrington, yesterday (Mon).

The signs - and the patrols - are aimed at publicising areas where there have been higher numbers of motorcyclists involved in accidents.

According to Sussex Safer Roads Partnership, 2,167 motorcyclists have been involved in crashes over the last three years, with 64 deaths and 733 riders seriously injured.

So far this year there have been 11 motorcycle fatalities, with five in West Sussex, one in Brighton and Hove and five in East Sussex.

Inspector Marc Clothier of Sussex Police’s road policing unit said: “These signs will be a continual reminder to all road users of our continued targeted enforcement action, in a significant effort to try reduce the motorcyclist casualties across Sussex.

“We would also encourage members of the public to report any road user who rides or drives inappropriately so we can target those individuals who present the greatest risk.

“We have got the resources to target those who go out to intentionally break the law, to get a cheap thrill and we will deal with those who commit this serious crime in the robust manner that it deserves."

Sussex Safer Roads Partnership spokesman Neil Hopkins said: ”We want riders to enjoy the roads of Sussex. But doing this safely requires both skill and judgement.”

He urged people to drive with respect for their own safety and other people.

Councillor Matthew Lock, East Sussex County Council’s lead cabinet member for transport and environment, said: “Here in East Sussex last year, motorcyclists made up a quarter of the total number of people who were killed or seriously injured on our roads.

“Considering this particular group only make up about 1% of all road users, it does highlight how vulnerable you are when riding a motorcycle.”

Bill Saker, of the Destination Triumph motorcyle shop in Washington, said riders would welcome even-handed enforcement, where both cars and motorcycles faced tighter enforcement.

He said: “There is a feeling we are underdogs and there is no respoct for motrorcyclists.

“People still have the attitude that if you ride a bike you’re some sort of hooligan.

“There are an awful lot of car drivers out there doing silly things as well.”

To report anti-social driving call Sussex Police on 0845 6070999 or visit the Operation Crackdown website at www.operationcrackdown.org.

The two men arrested on Sunday have been released on bail.