I'm using two 3S 5000 mah 20c in series in the vid so there's plenty of power but I'm lightening up a bit with w single 6S 2650mah 40C so we'll see soon enough how that does.
I agree on the tires but right now I think diameter is where its at since I'm about out of gearing options
Dude, batteries are NOT where you want to go light with a MMM. Seriously, current is where your batteries are falling down on you. You're running way higher gearing than is recommended, which you can get away with if you set things up right. But to run that gearing, you're going to pull a LOT of current, more than a 2650mah battery is going to keep up with. Bigger wheels are only going to make that situation worse. Eventually, you'll overdraw your batteries, and they'll blow up, or your ESC will burn. A higher C-rating, and a higher mah rating will allow you to pull more amperage while making less heat, and that will keep your truck from going up like a Fourth of July smoke bomb.
The other area where you're running high risk with those batts is that the MMM uses the batteries to sink current generated during braking. If you go to low in capacity(Mah) the batteries can't accept all that current, it sends it to the three capacitors in the ESC and burns them out. If your batteries don't puff on the spot, your next trigger pull will smoke the ESC.
Castle Creations themselves say that the ABSOLUTE MINIMUM battery ratings are 5000mah 30C. Where HPI got the 20C rating they have in their manual, nobody can figure out.
Lose your weight somewhere other than the battery. A carbon fiber chassis will save you some weight, and there have to be lighter, thinner wheels out there.
You can also cut some weight by trading down to some shorter shocks and lighter towers. Check this out, CF Hellfire towers mounted to the bulkheads on the tie-rod screw locations:
Or this, with Kyosho Inferno GT shocks and modded stock Savage X towers:
