Fairly certain this is a Triumph 5SW model,frame and cycle parts were same as the 3SW model,the timing cover appears bigger on the post card as fitted to 5S/6S/5H & Tiger 90 models,could be a head quarters bike with its petrol tank markings.
Nice one, thanks Steve. To my eyes the timing cover looks the same as mine?
I think the pre war 5S has the same timing cover as the 3S, 3SW etc. #E615. However I have noted that the 5SW has one less steel and one less cork clutch plates than the pre war 5S, having exactly the same clutch as the 3SW. Ron