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The Department of Transportation regulations for open face helmets are prohibiting the usage of open face helmets for motorcycle riders. Open face helmets can be used by bicycle riders.
Bicycle clip
Riders participating in the Tour de France use bicycles. They also wear helmets, cycling shoes, and clothing in their team colors.
To protect their heads in the event of a crash.
There are over 700,000 motorcycle helmets that are sold in the United States each year. Helmets are a requirement for riders in most states.
A tandem bicycle.
There is no standard collective noun for a group of motorists, in which case a noun suitable for the situation can be used; for example, a jam of motorists, a task force of motorists, a mob of motorists, etc.
A bicycle path is a path, segregated from other traffic, for the use of riders of bicycles.
Currently, the District of Columbia and 28 states motorcycle laws requires all riders to wear helmets. Twenty-seven states motorcycle laws require some motorcycle riders to wear helmets. Illinois, Iowa and New Hampshire do not have motorcycle helmets laws.
Yes, mc riders in the entire state of Ca. are required to wear DOT approved helmets although enforcement of the DOT requirement is virtually non-existent. Many riders including myself use what are commonly known as "novelty" helmets.
yes
Yes, there are professional bicycle riders.