I know it is about removing things and/or fitting lighter parts, but I find it quite difficult to do without compromising looks, functionality or spending lots of money. Some are quite good at it, though, and perhaps if I practiced a lot I could become that too. Looking at the CB400SF, which I am building at the moment, there really isn't a lot of parts I can remove. Well, a few kilos could be lost by fitting a lighter exhaust system, the footpeg hangers can be removed and replaced by something lighter, the sidecovers could go and save some grams, but overall I think it would be very hard to drop more than 10 kg without resorting to some serious high cost items like lighter wheels and suspension parts etc. But many times I also wonder where the weight is resting with some bikes. For instance, a Kawasaki Z400 twin weighs ever so slightly MORE than an MT07, despite lots of parts that must be lighter on the old bike. It is also amazing how the same Z400 can be about 65 kilo heavier than the XR400 from Honda. Could you lop 65 kg off a Z400 and still have a functional bike without totally re-constructing the whole bike? Probably not.