At around 9:25am on Saturday, June 5, officers were called to the A702, around five miles south of Elvanfoot after they were alerted that a motorbike had come off the road down an embankment.
The motorcyclist – who had last been filling his machine with fuel at a petrol station in Dumfries-shire on Friday morning – was pronounced dead at the scene.
Officers from the Divisional Road Policing Unit at Motherwell are continuing their enquiries and appealing to the public for information.
Sergeant Ryan McAuley from the divisional road police unit at Motherwell said: “We are working to establish when this crash took place. The 61 year-old man used a filling station in Sanquhar around 11:30am on Friday morning and we are trying to establish his movements after this time.
"He was reported missing by his family on Friday evening, when he didn’t return home.
“I would urge anyone who saw this black Triumph motorbike being driven on Friday, June 4 to contact officers. I would also ask any motorists in the area with dash cams to check back for any footage of the motorbike.
Anyone with information that may assist our ongoing enquiries should contact 101 quoting reference 1097 of 5 June.”