Good questions.
Weight: I cannot give an official weight until I receive final parts from my manufacturer.
Based off my 3D printed samples, using a full kit on a robot would add less than 4lbs to the bot.
*Side note: I believe we are losing almost 5lbs this year with the hardware updates if you were using older hardware
*FIX. I am a little rusty on the exact weights
Working to get the CAD up on the site, but here is what will be released:
https://grabcad.com/library/modulus-t811-1