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Old 11-28-2007, 03:58 PM   #76
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What did syndrome just say? He said that abusing certain chargers produces more voltage....and I firmly believe if it is not this issue, it will be another. Lipo will be the future, but we need to keep a lid on things, especially from a safety standpoint, that is my only thing.
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Old 11-28-2007, 04:04 PM   #77
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The only way to really make this work is saddle 7.4v packs and and probably 17.5 and 21.5 in place of 10.5 and 13.5. This will probably make everybody mad that they "have to buy different motors", but unless they can come up with a better voltage, that is what we have to work with.
That's a good idea...17.5 or 21.5BL w/ 7.4V lipo...it just needs to get tested and see how it works...
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Old 11-28-2007, 04:34 PM   #78
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Overcharging a LiPo will give it more voltage, with dire consequences. We can't rely on the fact that chargers are supposed to cut off at a certain voltage. That sort of thing can be tweaked, and someone could always force juice into a cell in NiMH mode after it finished. I know it sounds like it's far off, or nobody would be that dumb... but c'mon, you know how it goes in racing.

Charging LiPo at a higher rate than 1C does nothing for performance, and only hurts the cell's cycle life, as well as a more rapid charge. Don't believe the hype, charge at 1C no matter what your battery company says.

The issue I'm talking about is intentional overcharging, not charging at an absurdly high rate. Though that too should fall within the rules to keep things safe.
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Old 11-28-2007, 05:18 PM   #79
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BTW I meant 10A with NIMH, how else do you shoot the top of a cell into 1/2" of wood?
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Old 11-28-2007, 05:52 PM   #80
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yep!! I can't believe I have agreed with everything said on a thread dedicated to ROAR....

this is nice... productive conversation without one name being called... LOL

Jeff - thank you to you and Mike for your show on 11/5!! And yes, lets get together to work out a Q&A session so the membership gets to ask what they need to and hopefully we can give an intelligent answer. (I'm shy with public speaking though.. so I think I'll have our promotions director contact you! LOL)
I can call you names Dawn...NO PROBLEM....ok...how about:

Helpful? Patient? Progressive?

I don't think I am doing this right....LOL

Hope things are going well.

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Old 11-28-2007, 07:17 PM   #81
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Guys, the reason nitro 1/8th scale is so popular is because there is only one class, they are durable, and it doesn't take much maintanance to run for a whole day. When you show up to club race there aren't people there trying to run .18 buggy, .21 buggy, and .28 buggy. I believe that li//bl should head in the same direction. At major races only run two classes, sportsman & pro. If your a bad driver then run in sportsman, if your a good driver then run in pro. This way when you show up to your local club race there are 30 people in one class & not 10 people in 3 differant classes which makes for a much better race day. I also believe that 1/12th scale will work great w/ li//bl as well. People went to 4 cells because they wanted to run a lighter car and they could get plenty of power out of 4cells and a 10 turn mod. Well, lipos are light & you can get plenty of power out of a 10.5 bl or something. If you keep tcs at the same weight limit you will allow companies to make much more durable cars so that they can survive 20 minute mains. You have to give guys a reason to run on road other then come inside for the winter. Well, 20 minute mains & maintanance free cars would be a pretty good start. If you think 1/8th scale is hard to compete w/ now then just wain untill people start running li//bl 1/8th scales in the winter.
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Old 11-28-2007, 09:16 PM   #82
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I can call you names Dawn...NO PROBLEM....ok...how about:

Helpful? Patient? Progressive?

I don't think I am doing this right....LOL

Hope things are going well.

Art


Hi Advil!!! Tried to phone you a few months ago.. no idea why.. but I did.

Things are very well... good stuff happening in ROAR.. you'll see.
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Old 11-28-2007, 11:33 PM   #83
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There is a big push to get ROAR to beat the bushes and find the right lipo stuff.
ROAR is a sanctioning body, they make rules and run races.

You want lipo now? Get the manu's involved, they need to get the products to ROAR to be legalized and come to a set standards of construction.
Everything used in ROAR racing is supplied to them for consideration, ROAR doesn't make the products.

So get the lipo suppliers involved, they know what the specs should be set at and then get them to ROAR for approval.

ROAR has shown a big improvement just this year and is headed in the right direction.

Fred, ROAR # 11-109234
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Old 11-29-2007, 12:07 AM   #84
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Originally Posted by party_wagon View Post
Guys, the reason nitro 1/8th scale is so popular is because there is only one class, they are durable, and it doesn't take much maintanance to run for a whole day. When you show up to club race there aren't people there trying to run .18 buggy, .21 buggy, and .28 buggy. I believe that li//bl should head in the same direction. At major races only run two classes, sportsman & pro. If your a bad driver then run in sportsman, if your a good driver then run in pro. This way when you show up to your local club race there are 30 people in one class & not 10 people in 3 differant classes which makes for a much better race day. I also believe that 1/12th scale will work great w/ li//bl as well. People went to 4 cells because they wanted to run a lighter car and they could get plenty of power out of 4cells and a 10 turn mod. Well, lipos are light & you can get plenty of power out of a 10.5 bl or something. If you keep tcs at the same weight limit you will allow companies to make much more durable cars so that they can survive 20 minute mains. You have to give guys a reason to run on road other then come inside for the winter. Well, 20 minute mains & maintanance free cars would be a pretty good start. If you think 1/8th scale is hard to compete w/ now then just wain untill people start running li//bl 1/8th scales in the winter.

Nice! This man makes some good points here.
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Old 11-29-2007, 06:47 AM   #85
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Originally Posted by C_O_jones View Post
There is a big push to get ROAR to beat the bushes and find the right lipo stuff.
ROAR is a sanctioning body, they make rules and run races.

You want lipo now? Get the manu's involved, they need to get the products to ROAR to be legalized and come to a set standards of construction.
Everything used in ROAR racing is supplied to them for consideration, ROAR doesn't make the products.

So get the lipo suppliers involved, they know what the specs should be set at and then get them to ROAR for approval.

ROAR has shown a big improvement just this year and is headed in the right direction.

Fred, ROAR # 11-109234
ROAR must equally make it known that they want to legalize Lipo technology, and they need to first have a serious meeting to decide the rules and standards and spec for the lipo, and then let the manufacturers know...if the manufacturers know ROAR is seriusly pursuing Lipo lagalizationa nd they want the manufacturers to meet with them and discuss specs, they'd be all over that! When is ROAR going to step it up? When is ROAR going to have its first serius meeting to decide the specs and finally declare that ROAR approves lipo with such and such specs for 2008?

Its not difficult at all! All that needs to be done is have the meeting and decide the specs for Lipo- Rick Howart and Dawn Sanchez have already submitted: 7.4v, hard-cased, easy pluggin, safe, etc...which the Orion and CORE RC, TrackPower, packs already meet and have become very popular and the leaders in such a market. What is needed from Orion, CORE, Trackpower? Nothing! They already meet the specs! Its MaxAmps and SMC, THunderpower, etc...that are not hard cased, that will have to adapt and get their packs up to spec...but the big 2-3 already have a great safe product racers have been using for years now...so why not allow them already!?

Most cars today have been designed around the Orion 4800/CoreRC 5000mah Lipo size, 'cause they know how popular Lipo batts have become, so there is no issue there either! HB Cyclone, Tamiya MSXX, Tamiya 416, Schumacher MI3, Losi Type R, AE TC5, Xray T2'007 and '008 EU, Yok BD, etc, they represent the majority of the most recent cars today,and all can fit Orion 4800/COre RC 5000mah packs with no pblms...So no need to worry about manufacturers having pblms with redesigning their cars to fit these lipos...they have already done so, which shows their a step ahead and have realized and been sensitive to what drivers want, also...

ROAR has a green light here...its simple, and it can get done in one meeting if they are serious and really want to embrace Lipo technology. Its time for ROAR to show up and really make this happen...no more excuses!

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Old 11-29-2007, 07:15 AM   #86
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What a joyful thread !!

May I add: in regards to the spec and what's shows here so far, ie - hard case x dimensions x plugability - that the volume of the Li po pouch could be another determinant in the simplicity of the regulation. This volume would result from concideration of the expansion rates of Li po bags.

Just a thought.

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Old 11-29-2007, 07:16 AM   #87
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Hey Dawn and Rick Howart,

There is a way to get lipo to work in 1/12th, 5 and 6 cell touring car, and off-road, and reduce the advantage gained by abusive charging techniques. Speed controls could be limited on their output voltage to the motor, regardless of the power source input voltage.

If speed controls had motor voltage limited to 6.0 volts, it wouldn't matter how much voltage your pack had comming off the charger, the motor would only get 6.0 volts. 5 cell, 6 cell, 7.4 volt lipo wouldn't matter either. Also existing car designs wouldn't need to be changed. Could be an effective way to reduce to battery war perception that people have.

Obviously, older speed controls would need to be replaced or add-on limiters would need to be installed and enforced. Would have to find out from the speed control makers if something like that can be done effectively.

Do you think this idea would work or if it could be incorperated and accepted on an international level with Ifmar and the other organizations as a standard?

Mark

Last edited by Scrubb; 11-29-2007 at 07:58 AM.
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Old 11-29-2007, 07:46 AM   #88
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From the look of things you could talk about ROAR every episode.
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Old 11-29-2007, 08:15 AM   #89
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I've been avoiding this thread like the plague but it looks like one of the first ROAR threads in a long time that everyone's actually talking constructively about how to make things better.

For LiPo in 12th you can run at 3.7v. You will need a receiver pack but it's not like that's anything new to 12th.

I've run 12th at the single cell voltage and it's pretty interesting. There are good and bad points for LiPo in 12th. The good points are that single cell voltage will make the cars slower (13.5 is just a little slower than brushed stock). Another good point is running the same pack all day. The bad points are that it really screws up the weight distribution and mod will need to run at least a 3.5 motor. Cost is also a concern because a 12 cell single voltage LiPo will set you back close to $100 (mine's 5400mAh).

For what it's worth, I've also run at 7.4v and it's really not very good for 12th. The problem is that you can only fit about 2700 mAh in the car and it's a little sketchy on runtime. For me, LiPo is best when you're not even close to dumping (cells last longer).
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Old 11-29-2007, 08:35 AM   #90
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All this push for lipo is fine, but in a bigger picture, last I seen IFMAR has not embraced the lipo, and since ROAR is only a sanctioning body that tries to keep parity between the organizations for World competition, I personally think it would be irresponsible for them to start the push for lipo.

Most of the cars we have (TC) are of Euro influence and as long as that is happening, again the lipo is not being considered in current designs, only as a temporary fix, but not a specifically desgned car. Perhaps they would have to have US/Euro/NiMh/Lipo combo cars available.

The top drivers have as much of a influence in what is selling and being run currently as the manufactuers do and I've noticed a small pull back of the brushless racers, a few of the top people going back to brushed rather than brushless. With that and some of the bigger motor people bringing in more newer technology brushed motors, it appears that maybe before embracing all the NEW, we should sit back and see what is going to happen in the next while.
I only say this as its very simple to jump onto the newest, most current fad but its very hard to claw back the rules after they are changed.

If your current club wants to run the newest and next greatest thing thats very fine, but again, ROAR has to look at a bigger picture, which sometimes ties their hands, whether they like it or not.
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