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I picked up a couple of Duratrax Piranha 1900mh 7 cell packs. i charged them up, put one in my 5700kv brushless powered truck, and headed to the parking lot across the street. After a few minutes of light running, the trucks throttle was stuttering and I noticed smoke coming out of the truck. The pack was melted, and luckily no damage to the esc and rx. Should I cycle the packs a few times before putting one in my in my brushless truck? I'm scared to use the other pack since that one seemed defective.

you have just discovered the reason why you need to buy high quality matched packs. Your brushless motor is pulling too much amperage out of your batteries

I think i see li-po in my not so distant future.

the Mamba system will show you how poor your packs are...I have the 4600 and I put an older race pack in to practice and thought something was wrong with the car...studdering, poor performance overall. Switched to a newer pack and POW....lightning fast again and crazy power.

Basically you pulled too many amps out of those poor packs and they gave up the ghost.


You know all electronics are powered by smoke...cause when you let it out, they stop working.

i run mamba with a 9000kv motor, IB 4200 cells with the timing set to normal and it's good. So if you wanna pick up everyones old 4200 packs cheap while they switch to lipo it's worth it.
What kinda gearing were you running? You could also reduce the timing in the mamba setup..

I think i see li-po in my not so distant future.

If you are not going to race I'd seriously look into A123 cells. Much more robust than lipo, and can be charged in 15 minutes. They also have higher discharge rates than lipos. A good site for some info is http://www.thedunemaster.com. I plan to change over to them when they are more freely available in Australia.

Lipos don't like being stored fully charged for to long. If you use lipos and don't run them for a couple of weeks, make sure they are discharged to around 40-50% capacity, otherwise they will go off very quickly. I found this out the hard way, my main hobby is rc electric planes.

i have a 2.65 transmission 21t pinion 87t spur. i have been running some 3300mh ni-mh packs with no issues.i guess i'll try gearing a little lower and
lower the timing advance when running the cheaper packs.
i'm not sure when i'm getting the lithium.
my lithium charger is cheap and has a fixed rate of 1amp and i'm not too sure it will do so great charging a high capacity pack.so i'll most likely need a new charger also.