Harley-Davidson Endurance Riders - 1909

This image is of four Harley-Davidson riders who took part in a 388-mile Cleveland-to-Indianapolis endurance run that supported the first motorized competition at the Indianapolis Motor Speedway originally scheduled for August 13 and 14, 1909. The endurance run took place August 10 and this photo appeared in the August 12 Indianapolis News. I believe that the co-founder Walter Davidson, who took part in the endurance ride, is pictured second from the right, wearing a cap.
 
Unfortunately, no caption/cutline supplemented the photo, which is credited to Charles F. Bretzman. Some sources indicate that Bretzman was the first official photographer of the Indianapolis 500. You can find more information on the first day of the endurance run elsewhere on First Super Speedway.