Marcus, A trickle charger is really only of use when you want to maintain the charge in your battery, but because of its limited output current it won't be much good at charging a flat battery, in fact most trickle chargers will current limit if you connect them to a flat battery and won't charge anything. Most trickle chargers are less that 1A output which will take a hell of a long time to charge up a flat battery, if they can charge it at all. If you are going away somewhere for a protracted period, or know you wont be using you bike for some while, then a trickle charger might be of use (although I would question the good sense in leaving it connected whilst you are away!), but if you want to charge your flat battery use a normal charger, then disconnect it once its done its job. Why bother with two different chargers, seems like an unnecessary expense to me.