all sorted now guys, thanks for the input and explanations.
T'was the battery after all. Buy new one, charge it, fit it hit started button and vroom.... lovely.
As for the bumping (oo er), I've tried a couple of times, obviously with a knackered battery and i'm just shattered by the time I'm a hundred yards down the road, having to push the bike back to drive. I did have a cyclist stop once to give me a hand. And I dropped my CBR a week before a guy was coming to view and subsequently buy it. Luckily, just a scuff to the generator cover and a snapped indicator.
Cheers all.