Pit bull is tempting - but then I'd probably be the one in trouble, and doesn't seem fair on the dog!

Sugar in the tank also tempting just for the revenge factor, but the crazy thing is that the cost of the train regularly will actually probably work out more than the cost of the petrol taken. Its the annoyance rather than the cost (although that's starting to mount up). For now, we are leaving no petrol in it when parked, topping up from a can before making a journey, and have put a sign on the bike to that effect. Hopefully some fruitless trips will deter further activity.

Also thinking about getting a cover for the bike. Does anyone have any experience of whether they deter criminals? To me, it seems that it would still be obvious there is a bike there (and if they are past 'visitors', they will know it anyway) - but is it just a little bit more hassle that will make them move on, do you think???