The man was airlifted to hospital after a collision on the A49 in Leominster near the south Shropshire border on Monday.
It happened in Hope-under-Dinmore near Queenswood Country Park at around 4.20pm.
The motorcyclist was airlifted to hospital after his black Honda motorbike and a white Renault Kangoo van collided. He remains at the Queen Elizabeth Hospital Birmingham in a serious condition.
A spokesperson from West Mercia Police said: "The driver of the van was suffering from shock and attended A&E, the motorcyclist was airlifted to the QE hospital in Birmingham and remains in a serious condition.
"Officers would like to hear from anyone who was in the area at the time who may have seen the collision or may have dash-cam footage of the incident."
Anyone with information is asked to contact PC Prosser by email firstname.lastname@example.org or by calling 07773 054723.
Information can also be passed on anonymously to the charity Crimestoppers on 0800 555 111 or online at crimestoppers-uk.org.