Thanks for the snowbum link. Had the carbs off yesterday and set up the chokes as it all says. The bent cable issue was due to the fact that the cable pinch nuts which fasten the choke cable to the lever on the carb were installed wrong, and as such, they were held rigid which meant that the cables bent as the levers lifted. Ordered some new ones from motorworks, and the whole starting issue, coupled with the new battery, has greatly improved. Gonna fine tune today and balance the carbs, and then set about that pesky drain plug on the bevel box!