Did you look in the FSM for the bike? I know it isn't in color and we don't have a color-coded one for the K1 and up 450s, but the FSM does have one in it. Most of us here know the wire colors by heart so if you need to know a specific color's function all you have to do is ask. Here are some common ones.
Black - ignition ON power from the switch to the harness
Green - ground
Yellow with Red stripe - electric start wire from the button, delivers ground from the handlebars to activate the solenoid
Solid White (in headlight case) - low beam
Blue (in headlight case) - high beam
Light green - horn wire from the button, grounds to the bars
Light green with red stripe - neutral switch wire, gets ground at the neutral switch to turn on the bulb which already has power
Red/Red with white stripe - gets 12v from the battery to feed the wiring harness