I can't decide if mine's broken. If the bike's idling and I turn it to Off, how long should it take to stall?

It will still run for a bit as there is still fuel in the system not sure how long for but as an example i started my bike up and got a couple of hundred yards down the road when it cut out and i found that i had not turned the fuel on.

Hmm. I reckon my bike was idling for at least 5 minutes and still didn't conk out. I wonder if 200 yards riding uses more fuel than 5 minutes idling.

I left mine off for a week then rode it, got 2 miles up the road before i noticed and even then it didnt conk out. Easiest way to check is to turn fuel tap off and then disconnect the fuel hose. If fuel still comes out then youve got a duff fuel tap.

Yup! good idea.

As dont' forget if its still connected and you turn it 'off' you have fuel in the carbs and all the way up the pipe to the tank, quite a bit :)