Two suspected off-road bikers, neither wearing helmets, were injured after smashing into the back of a car on the busy Leeds Road in Huddersfield.
The crash happened near the RRG Toyota dealership at just before 5pm on Saturday.
Duty Inspector Tom Harrison, of West Yorkshire Police, said neither of the men was wearing helmets and the bike was unregistered.
It is believed the two men were on the same bike.
Insp Harrison said: “We don’t know what kind of speeds they were doing but a member of the public has crashed into the back of a black Toyota Rav 4.
“Both of them were taken to Huddersfield Royal Infirmary. Injuries included a gash to the head and a broken wrist.”
The smash caused some delays for motorists heading out of town as a police car with flashing lights was parked in front of the scene forcing drivers to navigate around it.