Thanks for the info Ironbark. I'll have to get the name of your hose supplier off you in a PM sometime.
I have seen people use PVC farm polypipe on the cheap, and the great thing is you can get the fittings to make the bend. But I find it a bit rigid. The same goes for radiator hose which has an extra layer of knitted fabric for reinforcement. Okay if you can get a secondhand length of radiator pipe to suit, but still the problem of being a bit too rigid for lawnmower use.
I notice some old mowers like Pope just used a straight length of rubber hose, connected to a cylinder apparatus on the end of the carby, then straight up the handlebars. Seems they just left the hose a bit loose so it could make a natural bend without kinking.