Cheeky cyclists may have been adding to the traffic problems in St Ives by triggering the priority traffic lights system meant for the guided bus.

Engineers from Cambridgeshire County Council have since altered the lights, which give priority to buses crossing Harrison Way heading to and from the town centre, to close the loophole.

Some cyclists had discovered that by riding towards the lights on part of the guideway route, one of the sensors would be activated and the lights would turn red on Harrison Way, allowing the bikes to continue without stopping.

The junction had been designed so that cyclists and pedestrians would use a traffic-light controlled crossing – a crossing that does not give priority to the detriment of traffic on Harrison Way.

A spokesman for Cambridgeshire County Council, which owns the busway, said: 
“An engineer went to adjust the lights after we got reports that cyclists were triggering them. Since the changes we've had no reports of this happening.

“The cycle route along the guided busway continues to be used by many cyclists. There's been lots of sunshine and using this cycle route is a great way to get outdoors to enjoy the summer whether you're commuting or cycling for leisure.”

Since the opening of the guided bus in August 2011, many motorists have complained that the journey times along Harrison Way have increased – a claim denied by CCC.

In 2012, the traffic was investigated by a transport and environment working group, made up of volunteers, which reported to St Ives Town Council that in the morning peak (7am-9am), the Harrison Way lights turned red every two minutes. The survey said each time the lights were red for an average of 21 seconds – creating a period of at least 23 minutes during the two-hour morning peak when vehicles were forced to stop.