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Old 01-02-2009, 03:05 PM   #1
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Default LiPo Conversion Help

I have an older RC10 Graphite Buggy using NiCd batteries and a brushed motor through a Novac Speed Control (sorry dont have model number with me). I would like to convert to LiPo and brushless. I have countless questions concerning this but will start with just a few basic questions.

1. can you use a Nmhd/NiCd 7.2/8.4v. charger?
2. do you need a special speed control?
3. what are the balancing connections and does this have to be done?
4. what would be a good battery - motor and possible esc combination?

The end goal is not to have the baddest car on the planet, just a car that can run with newer out of the box cars running LiPo / brushless combinations.

Thank you.
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Old 01-02-2009, 03:08 PM   #2
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NO, you can't use a regular nihn/nicd charger, it must be designed for lipos..
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Old 01-02-2009, 03:28 PM   #3
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You can use lipo battery with a brushed esc and brushed motor, the prob is brushed esc most probably doesn't have a low voltage cutoff that's needed to protect lipo from overdischarge. A two cell lipo (2S) shouldn't be discharged below 6v and most set their lvc slightly higher, 6.2 - 6.3v, to have a little safety margin.

Fortunately, you can add an lvc like a Novak Smart Stop that will protect your lipo from overdischarge. Overdischarge can damage a lipo to the point it will be ruined and become a poss safety hazard.

Balancing conns vary from manufacturer to manufacturer, there is no standard connection (unfortunately), there are 4 major types though, so its not an impossible issue to deal with. Cheap lipos seems to need more balancing than the higher quality, more expensive lipos, but practically all will need/benefit from balancing. Since you're going to have to get a new charger anyway, be sure to get one with builtin balancer so you can charge/balance at the same time.
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Old 01-02-2009, 03:29 PM   #4
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Older speed controls may be able to handle the voltage of a lipo, but the amps might not be supported. Better to get a lipo specific setup, something with the auto cutoff built in to protect your lipo batteries. Check out www.castlecreations.com, they make good stuff a reasonable price. Do your home on lipo's and balancing and what not. I balance mine only when they need it, meaning a cell is off by .1 or more.
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Old 01-02-2009, 11:47 PM   #5
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Is there a converter that you can plug into your nimh charger (for instance a Pulsar 2) to charge li po?
What about a cut-off switch, can u add one to a brushed esc? Just curious
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Old 01-03-2009, 12:17 AM   #6
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Quote:
Originally Posted by Klen420 View Post
Is there a converter that you can plug into your nimh charger (for instance a Pulsar 2) to charge li po?
What about a cut-off switch, can u add one to a brushed esc? Just curious
Losi does have some thing to hook up to a nimh, it says only use with certain chargers and batterys bla bla bla, I use it with a pitbull charger for six months now and love it.
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Old 01-03-2009, 12:32 AM   #7
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You will need a new charger for lipo's.

You can use a lipo and add a lvc with a brushed setup as long as the ESC can handle the lipo. Voltage is fine, as a user posted above it is the amps.

If it was me...
Go ahead and get new charger and maybe a 20c 2s lipo. Then just hook up your new lipo and see how it does.
If it can't handle the ESC you are gonna need a new one anyway
If it seems fine then you are good to go with the only worry is not to let the lipo run low. You can add the lvc at anytime.
Me, I only race at the track. I never run more than a 10 minute race. I know that my 6000mh lipo is plenty, I just charge after my heat. If you are gonna bash with it get the lvc. To get full advantage from the lipo's you will want to go brushless. More power, less maintenance, more power efficient, all that.


Your rc10 is capable of running with the newer 1/10 trucks. I was in a state race when my GT2 died on me. I switched to my $60.00 used RC10gt(which I had just bought the previous weekend.) I finished the Amain in 3rd(the engine flamed out about 10 times, I even had to come down off the stand and start it myself.) Took home a trophy

One other thought.... In my area 1/10 stadium truck seems to be fading both gas and electric. If you are gonna race make sure you will have others to race with in this class before you start dropping money. You will be spending some cash, so come up with your budget and then just prioritize your needs

Good Luck!
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Old 01-03-2009, 05:28 PM   #8
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Quote:
Originally Posted by Klen420 View Post
Is there a converter that you can plug into your nimh charger (for instance a Pulsar 2) to charge li po?
What about a cut-off switch, can u add one to a brushed esc? Just curious
Yes - like someone said earlier - losi makes a converter -

https://www.ssl-stormerhobbies.com/c...ns&pn=LOSB9607

And yes again, you can add a LVC to a brushed esc - they are made fopr specific lipo sizes - heres a 2S -

http://www3.towerhobbies.com/cgi-bin...&I=LXPGM8&P=ML
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Old 01-03-2009, 11:39 PM   #9
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sick! thank you

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Old 01-05-2009, 01:00 PM   #10
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does the Losi adapter balance?
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Old 01-05-2009, 01:24 PM   #11
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Quote:
Originally Posted by scwrod View Post
does the Losi adapter balance?
No, and it will only charge certain lipos -- and only charges them 90% full.....
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Old 01-05-2009, 02:57 PM   #12
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Thanks, that is what I thought and why I was pushing for "new charger".
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Old 01-05-2009, 10:09 PM   #13
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Ya, a better charger sounds right..
I was thinking of getting the intellipeak Ice.

1-10 Nickel-Cadmium cells (1.2-12.0V NiCd)
1-10 Nickel-Metal Hydride cells (1.2-12.0V NiMH)
1-4 Lithium-lon or Lithium-Polymer cells (3.6-14.8V Li-lon/Li-Po)

http://www.duratrax.com/caraccys/dtxp4170.html
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