I'm not sure. The photo comes from a UK site. You can have a look as below:
http://www.speedtracktales.co.uk http://www.sandspeedwales.co.uk http://www.silverdragons.co.uk I also got an email from Geoff Davison in WA who had this to say:
I'm fairly sure that the feature photo is of Fred Rist the BSA works rider from Middlesborough England. Fred was by far the best exponent of the beach racing that took place in England after the war, and into the 1960s. His BSA was extremely quick, and coupled with his slider technique, Fred was invincible on the beaches of Redcar, and Saltburn.
He was an extremely gifted rider who rode in the International six days, and also won many scrambles, and trials premier awards.