Question Who must wear a helmet while riding in Colorado? Answers All passengers Passengers under the age of 18 Passengers riding with an operator under age 18 Helmets are not required to be worn by any passengers. Explanation In Colorado, all operators and passengers under the age of 18 must wear approved helmets while riding. It is recommended that all motorcycle riders wear helmets. Take a FREE Practice Test Now This questions appears in the following tests: Colorado Practice Test