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Old 01-23-2009, 11:33 PM   #1
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Default Is Lipo to much power in 1/10th modified ?

With Brushless motors and a high end Lipo is the power/punch to much in 1/10th Modified 2wd and Truck ?

I'm asking this because we released a single cell Lipo for 1/12th scale and I'm thinking of trying single cell in mod offroad. I'm pretty sure it would make the motors smoother which should be good on many of the low traction tracks.

We could do a 12000 pack in the current ROAR hardcase.
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Old 01-23-2009, 11:54 PM   #2
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I dont think the lipo's are too much. I think a lot of people grossly over motor. Going to a single cell would require much hotter motors. I remember when 5 cell was being tested, in 2whl mod you went form a 12-13 turn to a 9 turn. Being that a single cell would only be 3.7v it would require at least a 4.5 to compare to a 7.5, maybe more. Wouldnt a reciever pack be required as well?
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Old 01-24-2009, 12:36 AM   #3
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takes about 10 seconds to dial the expo in.
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Old 01-24-2009, 02:43 AM   #4
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i'm currently running one of your 28c/5000mah packs in my mod (8.5 turn) truck and it is perfect.
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Old 01-24-2009, 02:57 AM   #5
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I don't think that LiPo can be too much for any category - you just use more turns on motor and you are in same place as with NiMH. Probably one cell won't be enough and you'll need to add lots of lead.
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Old 01-24-2009, 04:17 AM   #6
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I run Mod buggy and Stock truck (13.5) every weekend at our track. in mod buggy I run a 6.5 , 7.5 & right now a 8.5 .I have 4 of your 4100 24c packs (2 for buggy and two for truck) I personally don't think we need a single cell lipo. if our track gets a little slick I adjust the radio, speedo, and or throttle finger we run 6 min qualifiers and 10 min mains.
tacky clay with slicks most of the time.
Just my .02 worth.
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Quote:
Originally Posted by Danny/SMC View Post
With Brushless motors and a high end Lipo is the power/punch to much in 1/10th Modified 2wd and Truck ?

I'm asking this because we released a single cell Lipo for 1/12th scale and I'm thinking of trying single cell in mod offroad. I'm pretty sure it would make the motors smoother which should be good on many of the low traction tracks.

We could do a 12000 pack in the current ROAR hardcase.
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Old 01-24-2009, 04:38 AM   #7
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Yeah, wrong direction in my opinion. Why go to a higher current less efficient setup? As overall power is going up???

In general this is opposite of where the hobby is headed, many are bashing with 3 and 4S. While I have disagreed with the desire by some to take racing to a higher voltage, tradeoffs there as well, they do have a point, why go the other way, seems even less desirable to me.

This would require new higher current, more expensive I suspect, chargers for many/most of us. Granted, we wouldn’t need balancers, now that many have just invested in that. One of the most expensive items in the car, the speed control, a lot of development for smooth throttle profiles has occurred, would probably end up being redeveloped/repurchased. Same with motors, most guys have even more invested in motors, that would definitely be immediately obsolete/wrong. Stock and mod. New servos as well. Then the whole power the receiver thingy.

Let the 12th scale guys deal with it in my opinion. No biggie though, if somebody wants to run 1S wouldn’t it be legal? I mean, you can run 5 old school cells if you want can’t you? Like in the old 7 cell days, you could still run 6.

I don't think we are in the same situation as Touring cars. We get more than a heat or two at the big races!!!

So I vote no thanks.

Last edited by Dave H; 01-24-2009 at 05:09 AM.
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Old 01-24-2009, 05:30 AM   #8
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This is my personal experience:

NiMH 7,2 v and brusless is overpowered for 2WD. Going to 5 cells made it much smoother with a 6,5 turn. Even tried with 4 cells (4,8 v) and a 3,5 turn - which was super smooth. But the motor (and ESC I think) got very hot. And runtime is critical.

So LiPo (7,4 v) and brushless for 2WD is defo overpowered. Whichever solution provides the smoothest feel would be my favorite. And without anything geeting too hot....

I have a feeling 7,4 v is kinda ok, but we'd need smoother motors (maybe smaller?)
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Old 01-24-2009, 05:43 AM   #9
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Why not just go to a milder motor? I run 13.5-10.5 when needed, or a Novak Light series, a 17.5 even, problem solved. And I can practice for like 30 minutes, no heat issues at all.

Actually too much power is a big attraction in off road. Anybody remember the battery wars when we didn't have unlimited power in the day? Work that throttle baby!!!

Last edited by Dave H; 01-24-2009 at 05:59 AM.
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Old 01-24-2009, 09:01 AM   #10
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Good point Dave!

Lots of power and very easy to use, especially now with LiPo!

And we're doing 7 min heats in Norway starting this outdoor season. We might very well increase it every year... we prefer to "use" the extra runtime
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Old 01-24-2009, 09:33 AM   #11
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Thanks for the info. I agree using a higher turn motor is most likely the way to go but this could give us a different tuning option as I bet the power band would be different.

We will have sample packs to test and see what it will do in an actual car.

Novak has a Booster Circuit coming out that will bump the voltage up to 6 volts for the servo with built in cutoff.

I know a hotter motor would have to be used but so far in 12th scale this has meant lower motor temps.

For those who think weight would be lower it wouldn't as this pack would have the same number of cells as a 2S2P pack.
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Old 01-24-2009, 10:04 AM   #12
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Quote:
Originally Posted by aeRayls View Post
I dont think the lipo's are too much. I think a lot of people grossly over motor. Going to a single cell would require much hotter motors. I remember when 5 cell was being tested, in 2whl mod you went form a 12-13 turn to a 9 turn. Being that a single cell would only be 3.7v it would require at least a 4.5 to compare to a 7.5, maybe more. Wouldnt a reciever pack be required as well?
+1!!! some people need to learn to motor down for the track layout and conditions..Thats why the hottest motor in my off road box is an 8.5!

I think if we went to a single cell for mod we would just see hotter motors on the track for those people that always over motor( you know the guys that are fast as poop on the straights and then wad it up in every other corner from over shooting it) so it would change nothing other than we would have to buy different batteries for mod class, which I am in no big rush to jump up and go do.
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Old 01-24-2009, 11:31 AM   #13
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+1 on the (8.5) Motor,but think about it a 10.5 is plenty in 2wd buggy 2wd truck....
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Old 01-24-2009, 11:57 AM   #14
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I agree with just going down on motor and not worrying about a single cell lipo. I have been running a 8.5 in my 2wd for a while when I run mod and its plenty with a lipo. When I was running NIMH I would run a 7.5.
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Old 01-24-2009, 12:11 PM   #15
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I still want to test this as there might be some advantages. When racing indoor carpet offroad with a 7.5 Light motor I was really never squeezing the throttle with a 5000/28 pack. I was getting 27 minutes of runtime.


If I were to try 3.5 regular wire single cell Lipo maybe it would give me a better power band. Would be fun to see how much runtime I could get at 12000mAh.

It's easy for me to get our Lipo supplier to build some packs to play with so I will try and it and have afew others mess around with it to see if there is any advantages or use for it.
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