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Old 11-16-2009, 09:03 PM   #1
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Default Nihm on brushless

Untill I go totally lipo will I get more run time on my Nihm cells on a brushless system versus a brushed setup on Nihm?
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Old 11-16-2009, 09:14 PM   #2
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all depends on how u drive man. the way I do witch is balls out no. that's why I went all lipo. and I got all expensive lipo stuff at first and learnd my lesson and sold them all. I got all turnigy lipos and charger from hobbycity.com and it is cheaper than nimh and they are just as good as all the major lipo brands
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Old 11-16-2009, 09:18 PM   #3
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I plan on buying them. just waiting till I can get 4 and the charger all together. Was curious on if I can expect any longer run time when I switch to brushless until I get the lipos.
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Old 11-16-2009, 09:24 PM   #4
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yea the accucell 6 charger is awsome and it comes with deans plugs.
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Old 11-16-2009, 10:06 PM   #5
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I was running 18th scales when I went lipo - saw about a 25% increase in run time when the lipo was same mah as the NiMH. Due to the weight I was able to go about 25% bigger in mah as well and got about 40% more run time.

Sure you're familar with how hot NiMH gets when you run them - all that heat is wasted energy that you don't get to use, its caused by the NiMH's internal resistance. Lipo IR is way lower and with a good setup, the lipo may get warm enough you can tell they've been run. That extra energy you were wasting with NiMh and the heat contributes to the longer run times you get from lipo.
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Old 11-16-2009, 10:51 PM   #6
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The answer is yes. A brushless system is much more efficient than a brushed of similar power. Of course if you get the fastest brushless system you can find you will not do anything but kill NImh packs left and right, but if you are considering a mild setup similar to what your current brushed setup is, you will definitely see more runtime. Just remember with brushless that unless you have great batteries you will not get the full potential of the system.
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Old 11-17-2009, 10:33 PM   #7
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Quote:
Originally Posted by burnineyes View Post
The answer is yes. A brushless system is much more efficient than a brushed of similar power. Of course if you get the fastest brushless system you can find you will not do anything but kill NImh packs left and right, but if you are considering a mild setup similar to what your current brushed setup is, you will definitely see more runtime. Just remember with brushless that unless you have great batteries you will not get the full potential of the system.
by "kill nimh packs" do you mean destroy them or just run them down really fast?
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Old 11-17-2009, 10:44 PM   #8
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Well, both really. I meant destroy them, but they will not run for very long either.
Example;
I bought a MM7700 combo when they first came out thinking I wanted a really fast system. Well my 2 year old matched Nimh packs only lasted a few runs before they cooked all the shrink off the packs. My new stick packs melted first run, and I had to keep a close eye on my newer matched packs to avoid melting them. They worked just fine, but none of them lasted nearly as long as they did with lower kv motors.
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Old 11-18-2009, 05:19 AM   #9
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Seen same thing - a good brushless setup can be the death of all but the very best NiMh pacs. I've seen them vent rather explosively! There was a vid here - brushles edition E-revo, driving around in the garage and had a cell literally explode with a definite pop. Left a black soot mark under his car on teh garage floor.

Turn the punch control up and be easy on the throttle if you're going to try NiMh and watch temps!
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Old 11-18-2009, 10:32 AM   #10
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Yep, with a 10.5-17.5 the nimh cells seem to work great, but I saw a guy pop a nimh cell in his 4wd buggy with a mamba 7700. Sounded like a gunshot!I do know for a fact that this guy didn't balance his packs though, which may have been a factor.
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Old 11-18-2009, 05:49 PM   #11
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Reminds me - stick pacs are not recommended for brushless! The instructions for my Flux are clear about not using stick pacs to try and run a Flux (Castle 2200 combo). They show NiMH only in side-by-side as being what you can run as far as NiMH is concerned.

If you've ever repaired a stick pac with a dead cell, you know they use a thin, almost like tin foil, cell to cell connector and these will not take the current a BL setup draws even if the NiMH pac can supply it. ALso with side-by-side you can discharge these and equalize them so they can perform at their best.
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Old 11-29-2009, 05:29 PM   #12
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Of course you can use the NiMh with brushless, and they will be fine if the batteries are looked after. Anyone saying otherwise is either scare-mongering, or has shares in a Lipo manufacturer
Down in this part of the world Lipo is still catching on, there are still a lot of NiMh users. Brushless has however been here in full force for years.
I run 3 to 4 year old Orion SHO cells in my B44 with tekin 8.5 brushless and they are great. Sure, Lipo will be more power and better run-time, but it's nonsense to say NiMh either won't work well or are dangerous!
Just take care of the cells like you normally would, and there will be no drama.
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