I have been slowly sifting through the images found over xmas on the Stilltime Collection website having built a database so I can collect all the details the images allow and then linking those facts to information we hold across the site on the people bikes and places. The image below of a group of men taken around two of their motorbikes including a Matchless and Triumph with a UK Vehicle Registration MX 621 makes it is likely these are part of the British contingent at the event and has been identified as being taken at the ISDT 1935.

British riders with Matchless and Triumph 500 [BMX 621] with Irish racer and owner Robert Cecil Yeates at ISDT 1935
I am very grateful to the great granddaughter of RC Yeates, Jessica Fraser who helped with the identification of the rider and the bike’s owner. RC Yeates rode under a Motorcycle Union of Ireland license for Ireland on a Triumph 495. His race number was #223. Although loosing only 2 points on day 1 and 1 on day 3, Robert retired at the end of day 4 despite loosing no points that day. Robert appeared for the Irish Vase team in the Welsh based events of the ISDT 1937 and ISDT 1938 where further images can be found of him.