Lipo batteries in a brushed EMAXX?

[CrackerLife RC]

I'm thinking about getting Lipo batteries for my EMAXX, its got the EVX-2 16.8v ESC with low voltage detection. I'm told I can run Lipo batteries, but just need to take it easy when running. Any suggestions?

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[ajcar]

i run lipos all the time on brushed titans. no problems. im not a serious basher, so other members may have different opinions.

when you do decide to go lipo. measure your battery tray so you know what length/width/height of lipo to get. peace

[zippogeek]

There was just a thread about this earlier today...there's no problem with LiPos in a regular E-Maxx...knock yourself out!

[Gunamonkey]

What bumper do u have on your truck and where'd you get it? Looks BADASS!!!

[traxxasdeathwish]

i think he is rocking a proline summit bumper..???... but anyway i run 2 5200 2s lipo in my brushed summit 1/10 its more then fun. GO LIPO!!!!!!!!!

[M n M]

The new EVX-2 with LVD is completely capable of handling two 2s LiPo's. Even the older EVX-2 that doesn't have the built in LVD can handle 2s LiPo's (just use an external LVA).

As far as will the Brushed Titans handling the added punch of the LiPo's… IMO, thats a mixed jury. My personal opinion is that it's not the added power increase that potentially kills the Titans. It's the longer constant voltage and increased battery life that kills the Titans.

LiPo's have a slower discharge curve. They provide close to the max voltage until they near depletion.

NiMH's have a faster discharge curve. As soon as a fully charged NiMH battery is plugged in and the voltage begins to drop. The drop may not be as dramatic as standard alkaline batteries but the curve is sharper than the LiPo curve.

The stock NiMH batteries that comes with the E Maxx are 7.2v 3000mah 7 cell. They will actually charge up to 8.4 volts.

The 2s Lipo (rated at 7.2 volts but charges to 8.4) that fits the battery tray can be purchased in the 5000mah variety. Thats 2000mah's worth of additional run time per battery, 4000mah altogether.

So what does all this rambling mean to me… It not any added power that kills the Titan motor's because 8.4 volts is 8.4 volts. It's that the LiPo applies near 8.4 volts for an additional 2000mah's. The extended exposure to heat and stress is what kills the motor(s).

Kinda like instead of applying nitrous to a race engine in short bursts you apply it for a long duration.

Rambling is now complete.

[Zac_F71]

The newer E-maxx's have 8.4v 3000's that actually can hold up to 10v each..but like you say the discharge/voltage drop curve is much faster with NIMH

[CrackerLife RC]

It's the pro-line racing Ridge Line Bumper (Narrow). I've got another one.

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I've been running Racers Edge 8.4v 5000 mAh 7 cells in my truck, and then the stock 3000 mAh batteries.
Q: how much more runtime do you get with Lipo over nimh?

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[Trout150]

I've smoked 4 titans already with two 2s lipos both on the second run. I'm not even going to waste anymore money. Going to get mamba monster combo soon. Just a lil pricey. Although it did run like a bat. Lol.

Please watch for *s in your posts and edit out the inappropriate filtered words.
-ksb51rl

[zman2rwhd48]

After about 3 years of sitting on the shelf I pulled my Emaxx down off the shelf put in a new EVX2 with LVC and 2 5800mah Lipo's 15 minutes into the first run both Titans were smoking with temps at 227-225. Is there another choice for motors without spending $300 on the Mamba brushless?

[M n M]

After about 3 years of sitting on the shelf I pulled my Emaxx down off the shelf put in a new EVX2 with LVC and 2 5800mah Lipo's 15 minutes into the first run both Titans were smoking with temps at 227-225. Is there another choice for motors without spending $300 on the Mamba brushless?

Wow, 225°!!! I'm wondering if something wasn't binding or frozen, like a bearing in the tranny. After 3 years on the shelf it's possible a bearing ceased.

Wanna stay brushed… The DeWalt mod can be done for $50-$60. That includes the motor, pinion, motor mount and gear cover. A new mount and cover is not needed for this mod, you can do it with the original mount.

If you want BL… Hobbywing combos are a good place to start looking.

[Mikey76]

I've been running Racers Edge 8.4v 5000 mAh 7 cells in my truck, and then the stock 3000 mAh batteries.
Q: how much more runtime do you get with Lipo over nimh?

We had 15min run times on nimh and now getting 40-50 min run times

[CrackerLife RC]

Thanks.

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[Jakey]

2S LiPo packs will NOT inherently damage the brushed motors in an EMaxx. What will damage these motors is the the heat associated with long runtimes.

[CrackerLife RC]

I made a hitch to pull my Rc boats on trailers. And the pond is a nice walk from the house. So there's really no hard running involved.

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[Skink910]

Is it possible to cool the titans enough so you can run lipos without any question?

[jocoo26]

I'm sorry to wake up an old thread but I'm having this problem. I pulled old Emaxx off shelf (3906 I believe). Has dual 550 titan motors. Works perfectly fine with 2 NiMH batteries. I recently purchased (2) 7.4V Lipo and LVD and it will not run. ESC powers on and steering works, but no forward or reverse. I went back to the NiMH batteries and it works fine. Everyone is saying stock ESC can run lipo but its not working. ANY thoughts??

[Flux Capacitor]

I'm sorry to wake up an old thread but I'm having this problem. I pulled old Emaxx off shelf (3906 I believe). Has dual 550 titan motors. Works perfectly fine with 2 NiMH batteries. I recently purchased (2) 7.4V Lipo and LVD and it will not run. ESC powers on and steering works, but no forward or reverse. I went back to the NiMH batteries and it works fine. Everyone is saying stock ESC can run lipo but its not working. ANY thoughts??

No thoughts at the moment; although admittedly I had never tried LiPo's in a brushed system on the E-Maxx when I was running the twin Titans with the EVX-2 ESC.

I would however be interested in someone actually posting a video to prove the system can actually power on and work with the EVX-2 ESC and LiPo setup.

A two cell 7.4 LiPo when charged has a yield of 8.4 volts and two of them would equal 16.8 volts which is the nominal threshold for the EVX-2 and theoretically should work. Although as pointed out various times in this thread, you will probably end up smoking the Titan motors in a very short time.

[Richard@JP]

Excellent upgrade well worth doing

[jocoo26]

Does not have EVX-2. Has EVX

[Flux Capacitor]

Does not have EVX-2. Has EVX

That is the problem right there. The EVX ESC is rated at 14.4 volts so when you were hooking up your two 7.4v (2S) LiPo's, an over current was detected by the EVX ESC and disabled forward and reverse to protect its circuits. You were running roughly 2.4 more volts than that ESC can handle because each 7.4 LiPo is about 8.4 volts charged (4.2 volts a cell; of which there are two cells per battery) and the two batteries combined equal about 16.8 nominal yield output.

Matter of fact, I don't think the EVX (Novak) had over-current protection and you are probably lucky it didn't damage the ESC and to further extent, I'm quite positive it did not have reverse polarity protection.



When you mentioned that everyone was saying the stock ESC could run LiPo's; I'm quite certain they were referring to the EVX-2 or they were just not clear about what ESC they were using.

Point in case, the very first post indicates a EVX-2 was being used; not an EVX.

[cooleocool]

I want to take a second to point out that, while the manual posted does say "stick to 12 cells" ... Back in the day, Traxxas had an article on their website about how to modify your E-Maxx chassis so it would fit 14 cells. The box for the older E-Maxx trucks also said that the vehicle was capable of 30+ MPH when using 14 cells.