The bike is a 1916 Matchless Combination with a Vickers Machine gun
restored by the present owner, seen as the rider in the next picture
The photos were taken when the society held a muster at at Beamish Open Air Museum, Co Durham, this month.
Chris, the owner of the Matchless, also has a 1914 Triumph motocycle which he restored and runs (I'll post photos if I can get any)
Any interest?
Tom