iPod USB wire color

I'm wiring up an iPod USB cable to charge an iPod from batteries. But USB cables have 4 wires and I only need the positive and negative ones, not the Data- or Data+ wires. The four colors of wire insulation are pink yellow black green. Does anyone know which color wires are the (+) and (-) leads?

I don't know the colors, but the connector is well defined. I would trace it from a usb connector.

Standard USB pinouts have Vcc on Red, Ground on Black, Data - on white, and Data + on Green.

Your pink is probably a proprietary shade of red, and your yellow a proprietary shade of white.

Thanks, I'll start by trying Pink (+) and Black (-) the mix and match the others if that doesn't work.

Thanks, Dave, that's a good source. From that info it looks like computer USB ports will deliver between 100mA - 500mA. Is this true?

Careful here... there are some protocols in place: http://www.edn.com/article/CA220400.html