BlinkM MaxM 3 wire control

Alright, heres the problem. Im using a MaxM in a bike headlight. Ideally, the light will be sealed inside a case when I'm done. I have it set up so there are power wires for the barrel jack, and 3 wires left over. Ground is the bike frame, connected to the battery negative. There are 3 wires that arent being used. Can I program the blinkm with just the two data wires and ground?

Yup, you can do that. If the MaxM is already being powered, then all you need to talk to it is three wires: Gnd, SDA, & SCL. (aka '-','d','c').