Iron pins from sweeper trucks cause flat bicycle tires in Leeuwarden. That includes hundreds of flat tires each year, according to Tour Omrup Friesland Past bike shops in town.

These special vehicles remove weeds from the street. This is done using brushes containing iron pins. If the brushes lose their pins and cyclists ride on them, the tire should be replaced immediately.

“This has been a big problem for us in the last couple of years,” says Remer de Vries of bike shop Mint de Vries. “We get about two dozen flat tires a week. 80 to 90 percent of them are from a road sweeper.”

De Vries basically sees a flat tire coming when the road has just been plowed. “It’s worse in the fall, because then there’s more trash for the sweeper truck to sweep up.”

The problem of iron nails is not unique to Leeuwarden. For many years, cyclists in several municipalities have been complaining of flat tires caused by the brushes of weed trucks, as is the case in Almelo, Eindhoven and Enschede.

Not only are bicycle tires prone to punctures, but so are scooter tires, says Rene Visser of bike shop Lammert de Vries. “Every month, about ten motorcycles arrive here with an iron pin in the wheel. Replacing such a tire is much more expensive than replacing a bicycle tire.”

The sweeper trucks are from the waste processing company Omrin, which is leased by the municipality of Leeuwarden. Bicycle repair shop customers can contact Omrin for compensation, but this is only possible if they can prove that the damage was caused by the sweeper truck. Bike maker De Vries says this is not always possible. “You can find the pin on half the bikes, but not on the others.”

The company told Omrop Fryslân that it receives five reports every week, i.e. more than 250 reports a year. Three-quarters of reporters also receive money.

The problem of iron pins has been known to the municipality for years. In response, Leeuwarden informed Omrop Fryslân that alternatives have already been considered, but according to the municipality, steel brushes remain essential for proper weeding.

Amrin is also looking for solutions to limit the damage. According to Breuer Visser from the waste treatment company, it is a matter of pressing special brushes and plates.

“We put those plates in to keep the nails from slipping out,” he says. “There is always another sweeper truck driving behind us to clean the pins, but sometimes it gets further away and we lose them.” Therefore, it is not possible to completely prevent a steel pin from being left behind, Visser says. “We’re doing what we can.”