Aye Martin,
I too had a Candy Red ST70 back in 1974 and early 1975. The 35 miles from my bothy into Inverness on a Saturday could be eventful, with the engine nipping up after about 20 miles of throttle to the stop, 35mph "cruising"! Gave it 5 minutes to cool and completed the journey, no bother. Frugal on the old 2* fuel, changed the oil every 1,000 miles and that was about it. When going any distance on the gravel hill roads, I always carried a gallon of fuel in a plastic can on the carrier I had fitted.
To get the bike from Hertfordshire to Inverness-shire involved the "usual" trip in the guards van on the overnight train from Euston to Inverness, where the fold down handlebars came in very useful.
When crewing a Fowler AA7 ploughing engine, at the time, the bars were folded down and the whole bike lifted onto the coal trailer/water bowser for ease of transport and used as a "paddock bike" around the steam rally fields for the weekend.
Ideal for pootering on B, C and U roads and built up areas, stay clear of A roads and anything involving multiple lanes would be my advice, having, after a light shower, approached the Jack Olding's roundabout at Hatfield on the A1 heading south and "lost" the front end on the slick roundabout! I slid nicely in my PVC one piece rain suit into the middle of the multi-lane roundabout, spinning to face a 25 ton artic emergency stopping less than 6' from my legs!
Too close a call! The wee beastie was sold and the money went towards the purchase of a 1953 AJS 18S that would cope with travelling greater distances, on multi-lane roads.
Enjoy it, hopefully modern, high silica compound tyres will make it more stable in the wet. Good health, Bill