The group met at the state Capitol on Wednesday. They said modifying the law to allow people over the age of 21 to ride helmetless is costing the state lives.
A recent study by a University of Michigan researcher says 26 fewer people would have died last year if all riders wore helmets.
Heather Drake of AAA Michigan said, "The data is clear. The experiment is over in Michigan. Helmets save lives."
Michigan's American Bikers Aiming Toward Education says helmets should be a rider's choice. They say tougher licensing, motorcycle safety programs and driver awareness is more effective at saving lives than helmets.