That would explain the problem with the gear'sDo you know someone that has a Lipo with the same connector's that you could borrow long enough to see if it runs better? Please check the speedo to make sure that the Lipo cutoff is set.Also have you replaced the spur and do you have a couple of different size pinion's to try?Do not get real aggressive with the gear ratio until you see how it run's out.Am I missing something else guy's?
That 6900 is a LOT of motor in a Rusty,so easy does it,it is better to be easy on the setup than to start shredding part's.

I have a variet of pinions and spurs. I have in it now 19/90. Sadly, im in the military, and i only know of 1 or 2 other people at my base that run electric and they all have NiMHs... i think im just going to try a 2s lipo. if it works then awesome, if not, i still have good batteries for any future cars.

Let us know how it work's out and Thank's for serving

Ear's up and eye's wide open.

I've had fantastic luck with these in my 2wd 1/10 scale stuff. I have 6 of them now.

http://www.hobbyking.com/hobbyking/s...dProduct=14965

In my SC10 4x4, I run the GensAce 5000MAh, 40c, 2s from hobbypartz with good results.

Those batts are deffinitely a bargain. Im torn again as to what road to taking.I have been doing continuous research on this topic and have seen that the cogging problem could also just be my ESC. Apparently the sidewinder sv2 sport isnt all it's cracked up to be and may not even handle the 6900 cm36 motor it comes paired with(which is what i have). I dont know if i should just try an ESC that can handle the amperage my motor puts out, or buy lipos and a charger and fry the ESC all together lol. I wish i knew more about all this stuff....

Well i have finally come to the sad end of my search. Really dont know what took me so long to find this but im sure that some people who read this will think im just stating the obvious. On castles website for the mamba motors, there is a chart that says the 6900kv wont power a rusty..(or any other 2WD stadium or SC truck for that matter). The truth is the motor does not produce enough low end torque to get the vehicle up to speed. It has alot of top end speed but heavier truggies and trucks wont have good acceleration off the line. It would work if you were to push the truck forward really fast then pull the throttle. Sooooo lesson learned i guess... i think the biggest motor acceptable in this setup is the 4600KV motor and even then for it to perform smoothly castle reccomends the Mamba Monster or Mamba Monster Pro.. the SV2's capacitors dont have what it takes lol, mine turned black and chared the chip where they were seated in the ESC. I replaced the whole system with a SP short course master ESC and 11.5T brusless combo. Hopefully i have better luck with this system. i guess now atleast i have a high power motor for a future touring car. I'll just need to get an ESC and im set. Hope this helped. In response to the ORIGINAL post in this thread from Mike, LiPO's are probably the easiest...maybe not cheapest, but easiest cure to your cogging as they will supply a steady strong power source for the motor and ESC...