A leading bicycle advocacy group in Iowa is launching a campaign to end fatal bicycle crashes.

The Iowa Bicycle Coalition has started a petition addressed to the Iowa Senate president, Iowa House speaker, Gov. Terry Branstad, the Iowa Department of Transportation and Iowa Department of Public Safety.

“We demand an end to fatal bike crashes in Iowa and insist the Iowa General Assembly, Iowa DOT, and Iowa DPS work to improve bicycle safety,” according to the petition that had been signed by more than 500 people by Saturday afternoon.

According to the petition, seven Iowans have died in bicycle crashes this year and 48 Iowans have died in bicycle crashes the past 10 years. In half of the fatal crashes, motor vehicles failed to yield when passing the bicycle, according to the petition.

“We need a safe passing distance law requiring vehicles to change lanes to pass,” the petition states. “We need to end unsafe driving with increased penalties and appropriate reckless driving charges. We need safer bicycle facilities. We need enforcement of laws that prevent crashes.”

As part of the campaign, the Des Moines Register’s Great Bicycle Ride Across Iowa, or RAGBRAI, which begins next Sunday, will have a “Mile of Silence” to remember those who’ve died in bike crashes, Iowa Bicycle Coalition Executive Director Mark Wyatt said in an email.

Earlier this year, a proposed law to fine motorists $100 for not changing lanes when passing a bicycle gained steam in the Iowa Senate but stalled in the House.

Cycling advocates have long lamented soft penalties motorists receive when involved in collisions that injure or kill cyclists.

The petition is available online atiowabicyclecoalition.org/petition