Police are appealing for witnesses after the man, who was part of a group of motorcyclists, died during a fatal road traffic collision on the B6357 at Rough Hope Sike, near Bonchester Bridge, yesterday afternoon.
The incident happened around 12.30 pm, shortly after which the man was pronounced dead on the scene.
Sgt Paul Ewing, from the Road Policing Unit for Police Scotland, said: "In this incident, a motorcyclist, who was riding with a group of motorcyclists, left the road and collided with a tree.
"He was pronounced dead at the scene. We are appealing for anyone who may have information, or anyone who may have dash-cam footage of the incident, to come forward and help us with our enquiries."
Police Scotland can be contacted on 101, quoting incident 1880 of 21 September 2019, or report anonymously to Crimestoppers on 0800 555 111.