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Old 02-17-2009, 04:57 PM   #106
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If we don't want to dictate batteries mah sizes, etc. We will need to make heat and main times reasonable that the 5000mah standard as it has become on 4S consistently even with extreme hard driving makes runtime, IMHO. From what other manufacturers have posted based on what I recall, they have stated that we can expect about 13 - 15 minutes of runtime on a 5000mah 4S pack ( I think one was losi?) . I would say if they are saying a max of 15 minutes, assuming hard running, I think it would be better to be under there range, maybe 12 minutes max. This leads me to the 10 minute limit that I personally like.

As for a single tray, its not really hard to make it so most batteries fit. All you really got to do in the end is just use some form of weather stripping to take up the excess space when you put your packs in. Only issue there I see is guys who run different sized packs, which is probably minor when most will see this as a class where you need 1 or 2 batteries.
I can run for OVER 20 minutes with my Losi 4S 5000 pack. If you can't go more than 15, you're either driving too hard, or your gearing is wrong.
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Old 02-17-2009, 04:57 PM   #107
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Originally Posted by TonysScrews View Post
The best idea I've always agreed upon (and posted in this thread by Jhautz) is having a maximum weight rule on the battery. LiPo's are like fuel cells so regardless if you run 3S, 4S, 5S, 6S ....or 12S...you can only put so much energy (fuel) in a pack if the size is limited (by weight).
If the races are kept to 10min I don't see why the battery weight would matter. If someone wanted to run a lighter pack they risk dumping, while a 4s 5000mah will make 10min for sure. If someone wanted to run a 10,000mah 6s pack I could care less if they wanted to carry around the weight.
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Old 02-17-2009, 04:58 PM   #108
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I can run for OVER 20 minutes with my Losi 4S 5000 pack. If you can't go more than 15, you're either driving too hard, or your gearing is wrong.
Driving too hard LOL!

We are discussing racing right?
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Old 02-17-2009, 05:00 PM   #109
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I can only speak for our Lipos but it seems possible to make a bit higher capacity while keeping the weight the same. Our new 2200/40C flight pack is a bit lighter than our 2200/25C pack.

As we know making higher C rate cells will mean the cells will be heavier and have less capacity so this means the use of lower C rate packs maybe favored to make the runtime with a more powerful motor. This would not be good as lower C rate packs will have a shorter cycle life.

So a maximum weight limit on packs may not be the way to go as it may create more issues than solve issues.
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Old 02-17-2009, 05:08 PM   #110
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Driving too hard LOL!

We are discussing racing right?
Of course! But with "responsible throttle management" I was able to make a 15 minute main with that same 4S 5000 battery... in a Jammin Truggy running a MM 2200 system! It IS possible. Spinning your tires wastes energy, overshooting corners, using lots of brakes, sliding around corners in stead of rolling. All these are factors in RACING. Use your resources wisely, and you stand a much better chance at winning. I put a LAP on the nitro class my first time out with it! I was SANDBAGGING like crazy! If I had enough battery(6S 5000) I could've romped on them allot harder. Limiting battery size, would SNUFF that possibility.

I still think we should standardize a protective battery tray, and let the Racer decide what battery he needs for his specific situation.
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Old 02-17-2009, 05:23 PM   #111
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Originally Posted by R40Victim View Post
Of course! But with "responsible throttle management" I was able to make a 15 minute main with that same 4S 5000 battery... in a Jammin Truggy running a MM 2200 system! It IS possible. Spinning your tires wastes energy, overshooting corners, using lots of brakes, sliding around corners in stead of rolling. All these are factors in RACING. Use your resources wisely, and you stand a much better chance at winning. I put a LAP on the nitro class my first time out with it! I was SANDBAGGING like crazy! If I had enough battery(6S 5000) I could've romped on them allot harder. Limiting battery size, would SNUFF that possibility.
I hear ya' to a point. I've made 15min before with my Jammin buggy, but I ROLLED through the finish, and drove like it was a sunday cruise for the last 5 laps. I'm not nitro fingering at all, not overshooting turns, but I am on the throttle HARD and braking HARD at the last min just like you do in racing. My next races will be in the Nitro pro class and I can't just be easier on the throttle and brakes to save batteries. Thats not racing in my opinion..


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I still think we should standardize a protective battery tray, and let the Racer decide what battery he needs for his specific situation.
I agree, with 10min races..
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Old 02-17-2009, 05:25 PM   #112
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Ok does your Caster weigh 8lbs or less? If not then you're against the rules for they have an 8lb max.
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RCPro requires that the buggy weight is no less than 7lbs .05oz. I know I make that. I'm not sure if I make the 8lbs max for ROAR, but I'm sure it's close enough to shave it off

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IMO, ROAR for all of the great things it has done, has really alienated the racers w/ it's maddening decisions.

ROAR was WAY late to the game on brushless and lipo technology and then choose poorly on their standards (IMO). Now they are over compensating by trying to jump on 1/8 electric.

READ what these guys are saying! We are the driving force behind this class period! It didn't exist before we created it.

If ROAR makes poor choices again, it will only get ignored more so than it dos now.

Hard case lipos need to go away!

Weight limits are a joke!

Cell limits at this time don't make sense!
I sure hope you read your care and charging instructions for LiPos better than you read the OFFICIAL 2009 Rules before you quote things that are not there.

The Max Weight Rule was never voted out of ExCom for the Class.

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They were blasted for making rulings based on what they felt the class should be, and ignoring what was currently available. A ROAR rep posted in the Electric 8th Scale Conversions thread when this topic originally came up, and said that was their reasoning. They ignored the fact that nearly every current electric 8th buggy would be outlawed by their rulings. That's not healthy for the class or ROAR's image and following.

Rules are needed yes, but they need to be realistic to what is available.
I still stand behind my statement. And I am easy to locate if anyone cares to talk about it. One of our Responsibilities as Stewards of ROAR, is to ensure our Members and Affilitiates (MFG) have a framework to grow our sport today and in the future. Allowing an adoption of any and everything is poor leadership and is not in the best interest for anyone. For you to state we ignored a fact about the current 8th buggys is false and ignorant of the time and dedication by many (mfgs/committee members/racers/race promoters) put into recognizing this class. The committee and participating Affiliates are and were more involved with what is used in these vehicles than you understand, and included racers and builders of the electric buggys.

NONE of our decisions outlawed any of our Affiliate Partner vehicles or products, and in fact created a set of guidelines for new products to be accepted and used in our organization.
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Old 02-17-2009, 05:28 PM   #113
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I really don't see a need to limit motor battery setup *much*. Obviously you cant have somebody with a car battery and a swamp cooler motor running around blowing off marshals knees.

But,

The guy running the 200 dollar O.S. RG runs in the same class the guy with the 500 dollar O.S. Speed does for nitro.
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Old 02-17-2009, 05:33 PM   #114
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Dude you have a nice setup, I got it, but to say that "if you can't make 15min your doing it wrong" is kinda beating your chest a bit in my opinion. My 4s NEU 1515/1y MBX6 runs great, is not overgeared, is light, and runs cool all day long. I don't consider myself short changed, and I don't think the Losi 8E community does either. Sure there is a BETTER way, but you have to take into account what is reasonable, and I can tell you my local hobby shop does not have a 6s pack on the shelf. They have a 4s 5000mah though!

I run 20min mains with the nitros, doing a battery swap, and my swap time vs their re-fuel time makes for good fun legit racing. Racing a 15min ALL ELECTRIC main where some people like you have an expensive more rare setup that can make is a full 16-17min(before dumping), kinda leaves the majority out in the cold swapping batteries, while you cruise to an easy win. If I could make 15min, that would be no fun knowing I won because people couldn't.

One day maybe 4000mah 6s packs will be on every shelf for 100 bucks, but till then 15min mains seem unrealistic for most.
I ran 15 minute mains half the summer on cheap ass zippy 4s 5000 packs ($75.00) with a Neu 1512 2.5d motor (2050kv) geared to embarrass any nitro that ever dared try pass me on a 200 foot straight. Again, it boils down to choosing efficient setups to make 15 minutes. I stand by my point that 15 minute mains are easy if you are not choosing overpowered motors. The 1515 1y, 1515 1d, 1512 2d, 1512 1.5d are all great motors but they are much more demanding. The <2000kv setups are more efficient and provide more than adequate power for racing with rpms between 28-36,000. These motors aren't any more rare or expensive. It just doesn't sound as fun to get a 1700kv 3d or even the 1700kv Losi motor. castle is targeting bashers and their initial motor kv's reflect that fact. Tekin is coming out with more reasonable lower kv motors.

The problem is that many folks are running into this class without getting any kind of guidance as to what really works vs just some mfg selling them stuff. I will bet you if most people had a choice of running 15-20 minutes with no need for a battery swap, they would. However, they get lulled initially into the faster setups. 4s 5000 is the standard because that is what is being pushed, not because that is what necessarily works the best. My 5s packs aren't much more expensive than my 4s packs and damn sure ain't paying $250 bucks for a lipo anymore.

I ran a 1512 1.5d (3300kv) on 4s and could barely make 12 minutes with a 4s 5000 pack. Fast. Fun. Inefficient. I did what it seems most people do which is pick the fastest motor they can find and then learn that a 1/8 buggy running 60mph on a track is a little impractical. As they get serious about racing, they start dialing back the motor till they find a motor that allows them to run right around 38-42mph and to do so efficiently for a long period of time. Higher voltage and lower kv.

To say that most people can't get 15 minutes is a cop out imho. It is kind of like someone complaining they can run a 6 minute 1/10 main because the 9000kv castle motor they put in their b44 keeps overheating. No duh. Get a slower motor. Problem solved.
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Old 02-17-2009, 05:33 PM   #115
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in my eyes a 20-30-45min. nitro amain is to long, the cars get to strung out and there are really only 2-3 guys running on the lead lap at the end of a long main plus all the cars that go out early due to being broke, blown motors and so forth, long mains can be rather pointless. look at electric when running a triple 5min amain the racing is fast and close,very close why? cause you only got 5mins to get it done wich in my eyes makes you a better driver and its intence. so why not just do 7min qualifiers and 12min. mains wether its a trippile or single main you get better racing and everbody can finish. not everbody wants to buy a 5-6 cell pack and the 10th scale guys would rather just use their 2 2cell packs rather than buying a 5-6 cell just to race. me personaly i would rather run a shorter main 12 min. mains are plenty of time to get to the front and win a race. my 2cents
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Old 02-17-2009, 06:05 PM   #116
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Originally Posted by onefast8 View Post
My 2 cents,
I like the idea of 1/8 being a semi "open" class.

I want to see how these nicer 4s setups run this summer here in AZ (SRS) when its 115 standing in the pits. Dont get me wrong, I think they perform fine....for now.

I built my car on 6s, 1500kv just to be safe and im positive Ill be able to run my car when its 115 outside.

Cant we just have Kv limits per cell count rules? With like a max battery weight?

I also dont like the hard case thing because the puffy cell deal. I wish there was a type of battery tray that protected the battery but let you remove it to examine your pack.
I have only ran my car a few times but I know it will run 10-15 min main when it's 115 out I am over geared right now an still barley over 100deg on motor or speedo.
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Old 02-17-2009, 06:15 PM   #117
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Originally Posted by JDCrow View Post
I sure hope you read your care and charging instructions for LiPos better than you read the OFFICIAL 2009 Rules before you quote things that are not there.

The Max Weight Rule was never voted out of ExCom for the Class.



I still stand behind my statement. And I am easy to locate if anyone cares to talk about it. One of our Responsibilities as Stewards of ROAR, is to ensure our Members and Affilitiates (MFG) have a framework to grow our sport today and in the future. Allowing an adoption of any and everything is poor leadership and is not in the best interest for anyone. For you to state we ignored a fact about the current 8th buggys is false and ignorant of the time and dedication by many (mfgs/committee members/racers/race promoters) put into recognizing this class. The committee and participating Affiliates are and were more involved with what is used in these vehicles than you understand, and included racers and builders of the electric buggys.

NONE of our decisions outlawed any of our Affiliate Partner vehicles or products, and in fact created a set of guidelines for new products to be accepted and used in our organization.
Not to diminish the work put into the rules, but read the responses. Does it sound like there is much support for them?
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Old 02-17-2009, 06:16 PM   #118
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The only pack that I have had fail was a 2x2 put together and the cells broke through the hardcase on the end. The batteries were firmly in the car but the internal lipo in the hardcase was acting like a battering ran and broke of the plastic housing and broke a soldering tab that could not be repaired. I am not against a hardcase pack but ROAR approve should add a paint shaker test to its approval
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Old 02-17-2009, 06:48 PM   #119
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Always an interesting debate, but in my neck of the woods (Northeast) I suspect it is already a done deal. RC Pro has their 3 NE Division races on the calendar, running Carlton's rules, with 1/8th E being run at every race. Since RCP is the big deal in these parts, those will be the rules people around here will build to, and in turn that will influence what happens at the local level. Since Carlton got the rules right the first time, it sounds like a good plan to me. 10 minute max run time to me is the most important limit to keep on the class, and keep things from getting crazy. 5S/3300, 1600-1700, light car and you're good to go with a car that will handle well, run reliably and safely, and remain affordable.
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Old 02-17-2009, 07:47 PM   #120
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Originally Posted by thuren View Post
If the races are kept to 10min I don't see why the battery weight would matter. If someone wanted to run a lighter pack they risk dumping, while a 4s 5000mah will make 10min for sure. If someone wanted to run a 10,000mah 6s pack I could care less if they wanted to carry around the weight.
I agree as I'll never run a big heavy pack, but I'd rather have a limit on the packs than on the overall weight of the car as too many older cars are very heavy even with a light weight pack. You can't limit capacity as cells vary too much from one Mfg to the next. But using weight is very easy to tech.

Lighter packs do not have to necessarily mean you risk dumping. If I only need a 4S 3200mah 30C-40C pack to make my time, then that is all I am running. And I'm not suggesting cutting it close either.

For example: If you are racing a 10 minute main and use 250mah per minute, you need about 12 minutes of run time. The extra two minutes are for a practice lap or two and the final lap after the clock runs out. So that is 3000mah (12 * 250). Then if you don't discharge the pack beyond a conservative 80% then you would need a 3,750mah pack (3000 / 0.80). This is being generously safe.

I'd rather have my car light, balanced and set up to run as efficiently as possible. I don't want to spend a fortune on batteries with a higher capacity than I need. The batteries will be the most expensive part of this class in the long run and like Gary said above you need to keep this class affordable for it to grow. The way I see it in the scenerio above you'd be wasting your money on a 5000mah pack since 3750mah packs are a lot cheaper than 5000mah packs. Plus your car would be carrying and extra 150-200 grams it doesn't need to....LOL
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