George Brough in action on his own Brough Superior

Pictured above is George Brough riding to victory in the eight-day Austrian Speed Trials aboard his very own Brough Superior SS 100 Alpine Grand Sport in 1925. Brough personally guaranteed that each SS 100 was capable of reaching 100mph, something he verified himself on each bike he produced. This same motorcycle will be auctioned on December 15, where it’s expected to go for between $600 and $700,000. That would be a record for any motorcycle at auction.

Photos copyright Phillips de Pury & Company

Brough modified this SS 100 for competition in Austria by fitting Rexine panniers to hold his overnight luggage, a tool bag mounted below each pannier and fitted a Bonnkksen speedometer capable of displaying both time and trip functions. The engine was also tuned for performance at alpine altitudes and the bike is said to be longer and lower than the standard machine, although no specifics on this particular modification are given. Included in the gallery is Brough’s International Traveling Pass, issued by the Royal Automobile Club so he could ride the bike to Austria from England for the competition.

After the eight-day speed trial, Brough kept this SS 100 as his personal bike for a year, also winning the London-to-Edinburgh Trial and the Victory Cup Trial. He then sold the bike to Prince R. Chagla in India. Michael FitzSimons has owned this bike for the past 25 years and snapped the contemporary photos you can see in the gallery.

T.E. Lawrence was eagerly awaiting the delivery of an identical Alpine Grand Sport when he was killed aboard his seventh Brough Superior in 1935.

This motorcycle will be auctioned by Phillips de Pury & Company in Manhattan on December 15 as part of the Design Masters Auction.

There's 24 photos of George Brough's personal motorcycle in this gallery.