[JesseK]

For the original question:

Last night we weighed 2 minibot motors, 2 minibot motor mounts, the FTC battery, 1 TETRIX 18" Rail, and (2) 4" wheels. Total weight was between 4 & 4.5 lbs (scale only does 0.5-lb increments, but rounds up).

I will note that we do not plan to use the NXT or the motor controllers. We cannot find specs regarding the NXT's shock rating. Without that data, and given the open-field nature of this year's game, we will not put a $200 device on the bot and call it "reliable".