I agree with neilfein, I've never cut down any tools. If I'm just going somewhere for a day I just bring a leatherman, a small crescent wrench, and an allen wrench, all fit in my seat bag with a spare tube. On longer trips I just bring enough tools that I can completely strip down my bike and rebuild it should the need arise, I'm a bit paranoid. It really doesn't add up to much, 1-2 kilograms of tools. I'd much rather have full sized tools than suffer with less leverage to save a few grams.