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Maxamps.com WARNING

Old 04-20-2007, 04:43 PM
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y7deluxe
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Default Maxamps.com WARNING

I just purchased a 7.4v 6000HV 2S2P LIPO pack from maxamps.com Mine had the 12AWG, Thunder Power Taps and Out the top installed on top of everything. I got the first battery pack and it was 142mm long when they claimed it to be 137mm long. Talked to a tech over the phone and he told me that it was too long because I had the out the top added on. Sent it back, got the next one in the mail with it going out the side instead. That one was 138.9mm long. Called the techs back, they told me I had to smash some tape at the top of the battery down to get it to fit. My car has 138mm available for space, after pushing the tape down at the top, the battery pack was 137.9xmm long. Had to really ram it into the car to get it to fit, but finally it fit. Maxamps.com worked with me on all help that I needed. They refunded my money for the out the top and also refunded the shipping money from having to send the first pack back to them. I just wanted to make this post to warn others of the fitting sizes because they don't warn you of this on their website. Also, one thing that I forgot to ask the techs about was whether or not it'd be 137mm if I went with the 14AWG wire over the 12AWG... might be something to consider if you're pressed for space...
Old 04-20-2007, 04:48 PM
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Silentbob343
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Default RE: Maxamps.com WARNING


ORIGINAL: y7deluxe

I just purchased a 7.4v 6000HV 2S2P LIPO pack from maxamps.com Mine had the 12AWG, Thunder Power Taps and Out the top installed on top of everything. I got the first battery pack and it was 142mm long when they claimed it to be 137mm long. Talked to a tech over the phone and he told me that it was too long because I had the out the top added on. Sent it back, got the next one in the mail with it going out the side instead. That one was 138.9mm long. Called the techs back, they told me I had to smash some tape at the top of the battery down to get it to fit. My car has 138mm available for space, after pushing the tape down at the top, the battery pack was 137.9xmm long. Had to really ram it into the car to get it to fit, but finally it fit. Maxamps.com worked with me on all help that I needed. They refunded my money for the out the top and also refunded the shipping money from having to send the first pack back to them. I just wanted to make this post to warn others of the fitting sizes because they don't warn you of this on their website. Also, one thing that I forgot to ask the techs about was whether or not it'd be 137mm if I went with the 14AWG wire over the 12AWG... might be something to consider if you're pressed for space...
My pack was was spot on, but thanks for the heads up.
Old 04-20-2007, 06:56 PM
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Default RE: Maxamps.com WARNING

While I agree that they should state that certain options will change the dimensions of the pack. It sounds like they went out of their way to provide you with excellent customer service. I have ordered from MaxAmps a few times and recived super service as well.
Old 04-20-2007, 07:02 PM
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y7deluxe
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Default RE: Maxamps.com WARNING

Oh, I'm not doubting their service. I was just giving people the warning about the battery packs being larger than quoted when you have the "out the top" feature. But even after that it came 138.9mm and they quoted 137mm. Now the 12AWG instead of 14AWG may have had something to do with it. They told me over the phone to just push the top down and it ended up squeezing in... But ya... their service was amazing and they were willing to work with me in any way possible. Have yet to actually try out the battery though... waiting on a pinion gear to come in the mail.
Old 04-20-2007, 07:07 PM
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Default RE: Maxamps.com WARNING

i hate mailing stuff =\

but my lhs doesnt carry rustler stuf
Old 04-20-2007, 07:07 PM
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y7deluxe
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Default RE: Maxamps.com WARNING

wrong thread maybe wetzelpretzel425?
Old 04-20-2007, 07:21 PM
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wetzelpretzel425
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Default RE: Maxamps.com WARNING

no im just saying how can u handle to wait that long?
Old 04-20-2007, 08:56 PM
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y7deluxe
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Default RE: Maxamps.com WARNING

Well I had to get a pinion gear in the mail before I could run the lipo, so the extra wait didn't interfere...
Old 04-21-2007, 02:54 AM
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andrew222
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Default RE: Maxamps.com WARNING

how do the lipos perform?
Old 04-21-2007, 04:06 AM
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Default RE: Maxamps.com WARNING

I have "out the tops" on mine too and it fits actually a hair small in my Losi xxx-t. I had to put a little foam in there to get it snug. No biggie. So far, I am loving my MaxAmps 7.4 6000 Mah purchase. They last a long time and have been a breeze since I got mine. For the money...I'de do it again no problem.
Old 04-21-2007, 10:00 PM
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Default RE: Maxamps.com WARNING

Hey markhat, how are those runtimes?
Old 04-27-2007, 10:09 PM
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y7deluxe
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Default RE: Maxamps.com WARNING

Finally got to run my maxamps 6000hv 2s2p 7.4v today. It's run times weren't what I was expecting. I was under the assumption that LIPO's went 95-100% until they dropped below 3.8v per cell. Anyhow, after about 3 minutes of runtime the car began to slow. It ran for another 14 minutes after that and then reached its cutoff point of 3.3volts per cell. It went slower and slower as the voltage on the battery dropped. I'm not running anything special in my vehicle and that could be why. I'm running the Tamiya stock rs540 sport tuned motor (i think it's 27t) with a novak 12t rooster speed control. I was expecting run times to be at least 30 minutes. Very disappointed, but again, could be something with my equipment. I'm going to ask in the forums to see what others say...
Old 04-28-2007, 03:33 AM
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Default RE: Maxamps.com WARNING

You're cutting yourself short by not running it down to 3.0V per cell. 3.0V cutoff is fine provided they are balanced. I don't know of any lithium battery where the discharge curve is flat. LiIon and LiPo are nowhere near a flat discharge curve. I run 3-cell in my off-road buggy and even there the drop in speed over the course of the run is noticeable.

20 minutes brushed runtime is very good, you can't hope to do much better than that. With a brushless system, you can get 35 to 40 minutes on a flat surface.
Old 04-28-2007, 09:18 AM
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y7deluxe
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Default RE: Maxamps.com WARNING

Well my charger won't charge the pack up if it goes below 3.2volts per cell (TP-1010C, a Thunder-Power tech told me this over the phone) and my other mistake was comparing the vehicle to my cousins. He has a brushless system in his running the NiMH battery packs with longer run times. I figured his 4.5turn brushless would suck up more juice than my 27t brushed because it's much faster. Anyhow, thank you very much for your help on that matter, I'll be upgrading to brushless now
Old 04-28-2007, 09:45 AM
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Default RE: Maxamps.com WARNING

Brushless 'turns' are nowhere near equivelent to brushed ones. The low-end brushless motors are 10.5, 12.5 turns. It's a whole different scale. And 'stock' 27T has changed a great deal over the last decade. If it's made for racing, it's a current hog made for running 5 minutes off a NIMH battery.
Old 04-29-2007, 01:28 AM
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Default RE: Maxamps.com WARNING

I think you should be getting longer run times even with that motor. You may want to check your gear ratio. You may be over heating the motor which would explain the drop in power and shorter run times.
Old 04-29-2007, 01:32 AM
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Default RE: Maxamps.com WARNING


ORIGINAL: Access

You're cutting yourself short by not running it down to 3.0V per cell. 3.0V cutoff is fine provided they are balanced. I don't know of any lithium battery where the discharge curve is flat. LiIon and LiPo are nowhere near a flat discharge curve. I run 3-cell in my off-road buggy and even there the drop in speed over the course of the run is noticeable.

20 minutes brushed runtime is very good, you can't hope to do much better than that. With a brushless system, you can get 35 to 40 minutes on a flat surface.
If you want more than 50-100 cycles I would only run down to 3.3-3.5v per cell.
Old 04-30-2007, 03:35 PM
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y7deluxe
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Default RE: Maxamps.com WARNING

So stopping at 3.3-3.5volts per cell lenghtens the life of the battery.. would stopping at 3.8volts per cell lengthen the batteries life even more?
Old 04-30-2007, 04:15 PM
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Default RE: Maxamps.com WARNING

i dont know if this is true for lipo but I know that for nimh that the batteries need a couple of cycles before they give their full capacity
if these are brand new they may get better after a couple of charges

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