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Old 11-13-2008, 01:20 AM   #1
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Default LiPo query

After taking some advice from party_wagon (thanx) I`m looking to get a brushless motor and go 3s LiPo. Just a question or two...

Budget consraints dictate, i`m afraid.. So as far as motors go, i have my eye on a second hand Novak Super Sport SS4300 System wih ESC etc. However in the manual it says:

"4 TO 6 CELLS ONLY Never use fewer than 4 or more than 6
cells (7.2 volts DC) in the main battery pack."

Is this really true or is it something they say just cuz they are anal? Like telling you to wear bomb suits and helmets when you light fireworks?? D`ya think I can use 11.1v LiPo on this system? Also, I doubt that it has a LiPo cut-off.... Might bugger the batteries. But then apparently some batteries have built-in cut-off. You can tell that I`ve been goog`ling this stuff can`t ya

And as far as 3s LiPo goes: what would be a good charger to get? And it seems that batteries are not the same either. Any advice there?
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Old 11-13-2008, 02:04 AM   #2
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After more searching and reading other forums... It seems that the LiPo standard in off-road R/C is 7.4v, not 11.1v. Will the 7.4v really give me any advantage over my current 4600 NiMh set-up? I`m assuming here that you can use 7.4vLiPo on any brushless setup that says never to use more than 7.2v DC...

Would 7.4v be the way to go? Am I just being overzealous wanting to get the max power 11.1v anyway?
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Old 11-13-2008, 02:31 AM   #3
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Originally Posted by DirtMunky View Post
After more searching and reading other forums... It seems that the LiPo standard in off-road R/C is 7.4v, not 11.1v. Will the 7.4v really give me any advantage over my current 4600 NiMh set-up? I`m assuming here that you can use 7.4vLiPo on any brushless setup that says never to use more than 7.2v DC...

Would 7.4v be the way to go? Am I just being overzealous wanting to get the max power 11.1v anyway?
7.4V is equivalent of 7.2V. Your choice system was created before LiPo became available so it was not designed for your purpose. It can run but I do not know how long it will handle before it gives up.

Someone explained to me about advantage between Nimh and Lipo: Nimh will always have the better first punch then falter while Lipo might not have the initial punch, it will have a constant power delivery that might even better later in the run. Plus the Lipo is a lighter package compared to the Nimh.

You might have to add more weight to compensate the minimum weigh of the car but by having a removable weight option, you can actually spread the weight more than where the regular Nimh sits which can be much more effective that those "bricks" you used to carry.

I'm still in the Nimh bandwagon because I'm not too sure if I can take care of Lipo nor do I have safe room to store it.
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Old 11-13-2008, 06:00 AM   #4
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1st of all a good lipo is not dangerous. I suggest a smc 5000 or an orion. As far ar their benefit they have great rip if u get the right c rateing and mah. They also stay constant so with a bl system u have 0 power loss for a heat or 2 also u really only need 1 or 2 of them per car. Ive had mine for a year and it runs as good as new just balence it every so often. I love lipo and bl systems their is no maitnence
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Old 11-13-2008, 06:55 AM   #5
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Cool, thanx.. I`ve checked out those batteries online. Expensiiiiive would cheaper ones do the trick?

Also, I`m not too sure they`ll fit in my car. They look pretty rectangular, where my nimh are rounded. The car`s battery housing is rounded to accept the exact battery shape. Is this normal???
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Old 11-13-2008, 07:42 AM   #6
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Cool, thanx.. I`ve checked out those batteries online. Expensiiiiive would cheaper ones do the trick?
Orion and Fantom 3800 30C packs can be found on line for $80 each and both are amazing packs. Also for a bit more the SMC cant be beat.
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Old 11-13-2008, 07:47 AM   #7
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First off, I would not go with an old novak super sport brushless esc. Those esc's are smoke bombs waiting to happen (had 3 go on me) and there is a reason they are so cheap.

7.4 volts is the standard for lipo and you WILL notice a big difference over nimh packs and especially if you have been using budget packs.
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Old 11-13-2008, 08:09 AM   #8
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Right. Gotcha. I`ll scrap the novak idea

NOW... This brings me to another lipo point... if going lipo, why not go 11.1v and get screaming performance? Why isn`t everyone on 11.1v?
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Old 11-13-2008, 08:32 AM   #9
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Mainly because 11.1 volts is pure overkill in just about any 10th scale car. You can still get insane perfomance out of 7.4 volts that is controllable. Also, 3s packs cost more, don't fit in most vehicles without modification, and aren't legal for racing.

What car are you looking to go brushless in and how do you plan to use it? That will really determine what to look for as far as motors and batteries go.
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Old 11-13-2008, 08:33 AM   #10
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Right. Gotcha. I`ll scrap the novak idea

NOW... This brings me to another lipo point... if going lipo, why not go 11.1v and get screaming performance? Why isn`t everyone on 11.1v?
You can get a Castle Sidewinder 5700 on ebay for about $132 shipped. It's a great system. You cannot run 3s on it though. 3s is a lot of power to use everyday. The Mamba Max can handle 3s, but costs about $70 more I think. The motors are the same I believe. The Max just inputs more power. In a 1/10th scale 2wd electric car 3s is one the edge of just being outta control. Then again, that can be fun too.
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Old 11-13-2008, 08:37 AM   #11
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It's because 11.1v is simply far too much power for a 1/10th car unless you use a milder motor (like a 17.5), which isn't a bad idea. The SS speed control is not a bad unit at all, but they have their limitations. If you want REALLY fast and aren't racing have a look at the Castle Creations Mamba system. This speed control can handle just about any practical battery combo you would want and is relatively inexpensive. The 1/8th guys are using these with 5s (18.5v) setups so 1/10th should be a piece of cake.

If you're racing get a Novak GTB and buy the appropriate motor for your racing class with it. Don't get a 4.5 or something rediculous, you'll be totally out of control and get in everyone else's way.

Edit: Lipo is nice because you only need one pack. With Nimh you need 3-4 packs for a day of racing. With Lipo you finish your run and put it back on the charger, no discharging or cycling needed.
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Old 11-13-2008, 09:45 AM   #12
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Well.... I`m very new to all this RC business anyway. I`m not a racer (although that`s an in evitable step yet to be taken) so for now I just find things to drive all over and do just that, on my own. I would like to join a club very soon and go throw the car around the circuit a few times on a Sunday. If my motor choice is not race legal I`m not too worried when that step happens I can just get the correct stuff for the class. I just want some performance out of my car and have not got a clue where to start, being new to this. I`d like to get something decent however. Saves having to upgrade again in what will be the very near future.

At the moment all I`m doing is bashing around in a Mad Bull (don`t laugh ) but i`m looking at a new car (for obvious reasons) so if the motor combo I get is not compatible with the mad bull, I`ll just whack it in the new one. If nothing else, this will only motivate getting a better car sooner!

About the castle sidewinder: why the 5700? Why not the 6900 or 7700? Are those just too powerful for general offroad applications? I`m just trying to understand the reason for the choice. With the mamba max: which package would you recommend there, and why? I like the latter idea simply because should I ever lay my hands on a 11v battery I can stuff the thing into the car somewhere and chuckle away as the tires wear away in minutes. Just for a laugh!
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Old 11-13-2008, 10:21 AM   #13
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A Mad Bull?? Are you mad? Just pretend to install something that RESEMBLES horsepower and the tranny will croak.

You will definitely need a new ride if you plan on 3s lipo...

As far as the sidewinder/mamba and motors go, 5700kv is the most you could ever use on an offroad track. Plus, you can't use the 6900 and 7700 with 11 volts...the rotors would come apart spinning such ballistic rpm. The best setup for speed bashing and occasional racing is the mamba max with the 5700. 2s for racing and 3s for highway speeds.
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Old 11-13-2008, 10:30 AM   #14
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The Sidewinder 5700 may tear up a Mad Bull in time. Although, I put it in my Midnight Pumpkin and it held up fine thru one 2s pack. The 6900 and 7700 are only for the Mamba Max I believe. Also, they can only be run on 2s wherw the Mamba Max 5700 can run 3s. Overall the Mamba Max 5700 on 3s is the fastest possible combo as far as Castle goes. we're talking insane speeds there. Would probably rip the Bull apart. If you're wanting the most satisfying speed upgrade just get the Sidewinder 5700. You can run any type of battery with it and it's fully programmable. You can always get a Lipo down the road. If I am giving mis-information someone please correct me. I'm no expert, but I have a Sidewinder and a Mamba Max so I've read up on them a little.
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Old 11-13-2008, 10:45 AM   #15
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HA! I was never seriously considering 3s on the bull lol although it would have been funny to watch the gears strip

Thanx a heap for the info guys, it`s starting to make sense now... I think I`m going to start with a mamba max 5700, then lipo when I can afford it. and when the bull melts from sheer exhaustion I`ll get me a new bug

happy drivin`!!
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