Bike is a new CBF 250 2008 model. 900 kays on the clock. Took it out on a country run on the weekend. Trip meter showed just under 300 kays on the current tank, two sectors showing on the lcd fuel guage. Riding home down a slight decline, start to brake for traffic lights. I pull in the clutch for my first down change and the engine shuts down straight away. I take my hand off the clutch before I realise what's happened and compression lock the back tyre momentarily but didn't restart the engine. I pulled the clutch in, rolled on for a second or so, hit the starter button and the engine fires easily like normal. Is it possible that my braking down the slight hill, fuel sloshing forward in the tank has starved the carb? I would have thought that the carb would have enough in it to overcome this sort of thing, but perhaps I was that low on petrol. I filled it a couple of kays later taking 12 litres, but I didn't fill it completely as it's 1-2cm lower than the fill neck in a 14 litre tank + 2.5 reserve. Fuel tap was in normal position. Main reason I'm posting is what is the fuel tap all about anyway? Modern bikes seem to have trip meters and fuel guages making the point of a "reserve" a bit pointless (imho). Is the fuel tap a bygone of a former era the manufacturers still feel they need to include or is there still a real use for it? Am I better of running the bike with the tap in normal position and simply not let it get that low or just run the bike with the tap in the reserve position constantly? Thanks for your advice!