An important collection of 100 motorcycles, mainly pre-1950 machines, from Pamplona, Spain, will auction at the RAF Museum in Hendon, UK on February 27.
The Pamplona Collection is one of the most important groups of motorcycles assembled by a prominent Spanish private collector.
The extraordinarily diverse collection includes a brace of De Dion Bouton-engined machines, dating from the closing years of the 19th Century.
Nine four-cylinder models from the likes of Ace, Cleveland, Excelsior, FN, Henderson, Indian, Nimbus and Zündapp will feature. V-twin engined motorcycles will also ride onto the auction block.
Other historic bike models will include Harley-Davidson, Sunbeam, Vincent, Motosacoche, Peugeot, Matchless, BSA and, of course, Brough Superior in the form of a 1931 SS100.
Vindec, Wanderer, Acme, Rikuo, Böhmerland, PMZ, Griffon, Standard, Diamant, Laurin & Klement, Phebus and Mabeco will be among the rare marques represented.
The collection was assembled over the past few years for the enjoyment of the owner's friends and family, according to Bonhams.
It has been housed at various locations before coming to its purpose-built museum home, 12 months ago.
Almost all of the machines were in running condition at time of purchase, and have since been carefully stored.
"It is a pleasure to be offering for sale such a fine and outstanding collection of motorcycles," said Ben Walker, Head of the Motorcycles Department at Bonhams.
"The vendor has managed to assemble, over a relatively short period of time, a world-class collection of rare machinery and this sale represents a fantastic opportunity for the enthusiast and collector to acquire something really special for their garage."
The auction will be hoped to continue the success achieved by the sale of the largest single manufacturer bike collection, also at Bonhams, last November.
The collection of William Neutken, the greatest assortment of vintage BMW motorcycles in the world, was lead by a 1924 BMW 493cc R32, sold for an astonishing €109,250.