Hello Everybody!

A couple months ago i bought a new ESC for my Traxxas Slash 4x4 because the original burnt up last winter. Most car is stock except for a new more powerfull servo and the ESC. The ESC run perfect in rain(it's waterproof) while there's no snow. I love to run in snow and that's why i bought this ESC. But now the ESC is cutting power for the motor (velineon) after few minutes of driving and that's is kinda boring. The ESC is a Hobbywing EZRUN 80a rated 80 amps and i thought that was enough for the Velineon motor. in the meanwhile that semmed to be just a little wrong. The motor isn't as powerfull than before and it accelerates slower and don't get hot unless really pressed hard(like speedruns and snow) and when driving in snow on my road at home it suddenly stops running. The menu is still working and pushes slightly to the motor, indicates that the motor and ESC is working, but it won't drive, when i press the speeder. the Servo is running fine and the fan powered directly from the ESC is running normal.

The current setup is:
Traxxas slash 4x4. 3 years old in a month or so.
motor, receiver and sender is 3 years old
The rotor in the motor where broke 2 years ago in an attempt to go lipo. (destroyed rotor inside motor, lots of gears and rotors from diff to wheels)
since that i stopped driving lipo.
The battery is a new 4500 Mah 8.4 Volt Nimh with Traxxas connector.
The wheels are just a bit bigger than the stock ones (1 cm in diameter).
The gearing is as low as it can be (13/56), so that is not the problem.

What i've found out so far is:
1 other guy has experienced the same and thought that is was because of over amping the ESC so the relay turned off in a couple of hours.
This ESC may not be able to fully power a Velineon motor. Other recommend 100 Amps.
Nothing in the car is hotter than it should be at any point (max 40 celsius for battery and both motor and ESC is about 30 - 35)

Is it over amping? is the battery capable of deliver over 80 amps? The ESC is not hot when the fan is running, so i continue running the car, thinking that it won't hurt? Please stop me if i'm wrong. Is it possible to measure wattage or something with normal gear for a normal guy without acces to expensive equipment? I am planning to get a multimeter to measure resistance in the battery so i can get a max amp that the battery can deliver. Is that correct thought or will it be without meaning or a useless info?

i've just started high-school so sorry for my bad english Hope you guys can understand me.

EDIT:
Today i was running again, but with low battery. The ESC did cut the motor after just 1 minute or so. Is it the ESC cutting off power because of too low voltages? I will try charge the battery and go out again and run to see how long it last now.

EDIT 2:
After reading some post from other people having problems with their reciever i thought if it maybe was my receiver that didn't get the power it wanted and then gave a weird signal. I tried putting a 6V battery on it and it worked perfect. if i pulled it off and turned off and then turned on the ESC without battery the problem where there again. So a BEC battery was the solution for me.

From my experiences, velineon motors don't get along w/other speed controls....

I'm not sure but is your speed control for sensored motors? I believe the Velineon is sensorless, which will cause problems.

Thanks for answering
No, the neither the Velineon or the Speedcontrol is sensored.