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Old 12-28-2008, 11:54 AM   #91
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I don't get the big argument over lipo guys. When this thread was started it had nothing to do with Lipo vs. Nimh weight difference. It was about the ROAR min 1/12th weight in regards to the brushed vs. brushless 4-cell application.

I'm a huge lipo proponent but the lipo 1/12th guys need to give it a break on this thread cause lipo AIN'T happen in ROAR 1/12th at any level 4 or 5 event in 2009. In fact I can't really see it happening in ROAR anytime soon as a combined class either. If and when it will most likely end up separated until such time that it truly becomes the standard as defined by racing ROAR members and not mfrs or their sponsored drivers.

If the lipo guys want to argue weight and performance, by all means do so, but please do it in your own thread and stop jacking this one.
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Old 12-28-2008, 12:23 PM   #92
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Most guys aren't letting off the throttle for eight minutes now. do you believe slowing the cars down will help things?



If you WERE pushing LiPO for business reasons, I could understand. If you're not an active 1/12 scale racer, then I can't figure out why you ARE pushing this... and while you're at it, you make all these proclamations about "just slowing the cars down" and "no need for saddle packs, t-bar cars aren't popular" etc. Why not leave it to guys who actually race 1/12? Your "screw everyone who can't easily adapt to a single brick 3.7 cell" attitude would seem to be ALL about profit, and not about anything else. I don't see how pushing a technology that takes roughly half the existing 1/12 cars out of the picture can be something positive for the class.



AMEN!! The way things seem to be going, I expect more people will be LEAVING 1/12 than will come in.
If it were up to me I would rather everyone in every class runs sub-c cells that way we would be selling allot more packs and our profit margins would be higher.

The fact of the matter is sub-c cells are on the way out and we decided to offer an alternative. We have 3500.00 invested in this pack and the reason we did it is we beleive this will be a good solution. If we wrong we lost 3500.00 and we tried to be part of the solution. If it works out the investment we made will repay itself.

Just because I don't personally race 12th scale doesn't mean I don't know and understand what can and can't help this class. After all it's still RC car racing and some of the issues in racing will always be the same.
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Old 12-28-2008, 12:29 PM   #93
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And I hate to be a killjoy, but I see a problem with single cell saddle packs. The only way you could do it is to put 2 single cells on either side of the chassis, and connect them in parallel. What's to stop someone from connecting them in series?

Tracks should be checking for overcharging of Lipos so when they do check for this running a pack in series would show 8.4 instead of 4.2.
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Old 12-28-2008, 12:41 PM   #94
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I don't get the big argument over lipo guys. When this thread was started it had nothing to do with Lipo vs. Nimh weight difference. It was about the ROAR min 1/12th weight in regards to the brushed vs. brushless 4-cell application.

I'm a huge lipo proponent but the lipo 1/12th guys need to give it a break on this thread cause lipo AIN'T happen in ROAR 1/12th at any level 4 or 5 event in 2009. In fact I can't really see it happening in ROAR anytime soon as a combined class either. If and when it will most likely end up separated until such time that it truly becomes the standard as defined by racing ROAR members and not mfrs or their sponsored drivers.

If the lipo guys want to argue weight and performance, by all means do so, but please do it in your own thread and stop jacking this one.
Thank-you. On all points!
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Old 12-28-2008, 12:43 PM   #95
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Not that it's part of the weight discussion but all you need is a cheap volt meter to check the voltage of the packs. The tracks should be teching this on all Lipo's to prevent overcharging anyway.

As far as weights are concerned I think the weight for all NiMh should go to 865 grams.

LiPo should be treated as a different class and should have a lower weight. Where the two classes are mixed the clubs should come up with what weight LiPo should run. As soon as there are enough racers to run more than one class we should set a better weight for LiPo as it's own class. It's not a big deal to have a ton of lead on a sedan and it's not a big deal to throw lead on a 12th car.
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Old 12-28-2008, 12:49 PM   #96
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I'm ok with 800 grams because that's what my heavy 12R5 weighs in at with brushless and a lipo battery! Otherwise it is 6 ounces too heavy
I'm working on getting my DB12 to the 800+ weight on the lipo. I was way under that Friday and it's twitchy as hell. You or Phil could have run 8s with it, but it's waaaay to much for me right now. My temps were around 115F and I had plenty of speed, so weight should be a good thing for me.

I should have let you run it. Tire wear seemed to be almost half... wrong thread.
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Old 12-28-2008, 01:03 PM   #97
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OK, to get back on topic...

The weight problem in 12th is very little to do with BL against BR, and more to do with the weight of packs and cars going up. In 2006, 3300 cells were surpassed by 3700/3800 cells that weighed 65g each. Even then, most cars weighed in about 820 to 840 grammes.

Today, a 4600 cell weighs 72g, so we've gained 28g on cells alone. Compare that to a BL motor that weighs little more than a BR - about 10g according to my scales, and a speedo that weighs 7g more, again according to my trusty scales. 17g from BL and 28g from 4600s - this isn't a BL problem.

Look at the cars! Since the trusty AE RC12L4, every car I've had weighs about 20g more, and I am guessing that the 12R5 will be even more than that - side shock, adjustment for centre shock, links, front end... My BMI weighs 20g more than my old 12L4! The cars have also contributed to the weight gain.

If weight were that important, then the lightest car would always win. The joy of 12th is that the best driver with the best set-up always wins, whether at Nationals, Worlds or at the Club. BL technology has the least effect on weight increase, and will shortly be back where BR left off.

And if I can get my car down to 830g (and I can) and I will be upgrading to later motors and speedos that weigh less, why should I have to carry 40g of lead to make an arbitrary weight limit? At least the 800g limit keeps costs down and makes tuning easier. Imagine all the "BL and LiPo makes racing easy" brigade who now have to learn to move weight around for the best handling!!

Leave the weight alone, there's more important things in 12th IMHO.
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Old 12-28-2008, 01:44 PM   #98
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This has been such an interesting thread to read. It's classic b-school stuff.

1/12th scale is a well-established, refined class of race car with a dedicated core of users who defend its virtues with great conviction. This group has more or less accepted brushless technology as a sustaining innovation. Sustaining innovation provides incremental improvement over existing practice without requiring major overhauls of the model.

But lipo...lipo is clearly a disruptive innovation as applied to 1/12th scale. It ignores the current definition of quality, in this case that 1/12th scales have been designed for sub-C's and work best with them (the WGT guys adopted the same definition and designed the car and class around what works best: engineers, right out of central casting.) Lipo batteries, on the other hand, create a new definition of quality around convenience, reliability, and by extension, lower cost. As a sidenote on branding, is there a tidier example of a product "othering" it's competition? Lipos are convenient, reliable, and cost-effective. NiMH's have been redefined as temperamental, uneven in quality, and expensive. Someone in the lithium industry should receive an award for kicking ass in postmodern marketing strategies.

In sedan, lipos have been integrated with relatively minor disruption to past practice (In hindsight, all the angst seems trivial.) 1/12th scale cars, as a platform, don't afford the same opportunity for integration without rethinking fundamentals of the class. And now, the battery tail begins to wag the dog, as it were. This refined, proven, affordable racing platform risks being redefined by its battery. Regrettably, to its detriment.

And to cap it off, the powers that be tell us not to worry, things will stay the same, and anyway, we're off subject.

Can't decide whether to or
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Old 12-28-2008, 01:56 PM   #99
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And I hate to be a killjoy, but I see a problem with single cell saddle packs. The only way you could do it is to put 2 single cells on either side of the chassis, and connect them in parallel. What's to stop someone from connecting them in series?

Umm the rules, fellow competitors, the fact the dude will dump half way through since hes got a 2000mAh 7.4v pack... etc...
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Old 12-28-2008, 05:31 PM   #100
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I'm working on getting my DB12 to the 800+ weight on the lipo. I was way under that Friday and it's twitchy as hell. You or Phil could have run 8s with it, but it's waaaay to much for me right now. My temps were around 115F and I had plenty of speed, so weight should be a good thing for me.

I should have let you run it. Tire wear seemed to be almost half... wrong thread.
That's ok if everyone only went by what Roar says the hobby would be dead.
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Old 12-28-2008, 10:16 PM   #101
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Scott, at my local track (which also happens to be Trips local track) we have seen the exact opposite. People are switching in droves to touring car, thanks to brushless motors and LiPo batteries. Thanks to the lack of maintenance necessary, people are actually enjoying racing now. 1/12 scale has seen a decline because you cannot run LiPo in that class (at least according to the track owner). And more people want to run brushless in 1/12, but don't want to deal with the weight penalty.
Jim, we're pretty much all running brushless now in 1/12 at 360, I might have been the last bruhed hold-out, but even I've made the switch. LiPO's are allowed for club racing, just not for the big events (I may be wrong, but I think we even had a deviation for the regional; allowing the 3.7 LiPO for 1/12, but you would have had to run with the 17.5 AND make the ROAR weight, which would have effectively crippled a 3.7 car.)

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The problem is right now we're in the middle of a huge transition, and there are no easy answers.
I couldn't agree more.
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Old 12-28-2008, 10:42 PM   #102
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And I hate to be a killjoy, but I see a problem with single cell saddle packs. The only way you could do it is to put 2 single cells on either side of the chassis, and connect them in parallel. What's to stop someone from connecting them in series?
Two replies to this so far... one mentioned the voltage check at tech would reveal it, another mentioned that connecting the cells in series would halve the capacity of the pack and cause a mid-race dump...

I'll offer a third observation... just a glance at the spur/pinion combo would reveal it... no way will you be able to gear a 13.5 anywhere close at 7.4v to what everyone else does running 3.7. It would be instantly apparent.

tiny spur/huge pinion = legal
big spur/small pinion = cheating

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Old 12-29-2008, 05:58 AM   #103
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OK, to get back on topic...

The weight problem in 12th is very little to do with BL against BR, and more to do with the weight of packs and cars going up. In 2006, 3300 cells were surpassed by 3700/3800 cells that weighed 65g each. Even then, most cars weighed in about 820 to 840 grammes.

Today, a 4600 cell weighs 72g, so we've gained 28g on cells alone. Compare that to a BL motor that weighs little more than a BR - about 10g according to my scales, and a speedo that weighs 7g more, again according to my trusty scales. 17g from BL and 28g from 4600s - this isn't a BL problem.

Look at the cars! Since the trusty AE RC12L4, every car I've had weighs about 20g more, and I am guessing that the 12R5 will be even more than that - side shock, adjustment for centre shock, links, front end... My BMI weighs 20g more than my old 12L4! The cars have also contributed to the weight gain.

If weight were that important, then the lightest car would always win. The joy of 12th is that the best driver with the best set-up always wins, whether at Nationals, Worlds or at the Club. BL technology has the least effect on weight increase, and will shortly be back where BR left off.

And if I can get my car down to 830g (and I can) and I will be upgrading to later motors and speedos that weigh less, why should I have to carry 40g of lead to make an arbitrary weight limit? At least the 800g limit keeps costs down and makes tuning easier. Imagine all the "BL and LiPo makes racing easy" brigade who now have to learn to move weight around for the best handling!!

Leave the weight alone, there's more important things in 12th IMHO.
All good points, however if you look at last years Nationals in Omaha you will see that brushed 1/12 scale stock was the prominent upper qualifiers! Hmmmm wonder why!
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Old 12-29-2008, 06:42 AM   #104
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Umm the rules, fellow competitors, the fact the dude will dump half way through since hes got a 2000mAh 7.4v pack... etc...
We used to make eight minutes no problem with 1200 mah nicads and mod motors that were less efficient than the 13.5's of today. We made time with 14 turn brushed motors and 1700mah Nicads, we made time with 2000mah nicads... I don't think making eight minutes with a 2000 LiPO would be an issue.

I'm not so sure that anyone who has been racing 1/12 for less than ten or fifteen years will understand how to drive to make time, but believe me it can be done. One of the things I LOVED about 1/12 racing was the fact that you couldn't just tear into the throttle for eight minutes... you'd not make it past six doing that. The idea was to go as fast as you could without usiing up the energy too soon.

Some saw dumping as a "problem", others saw it as part of what made 1/12 racing great. Count me among the others.
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Old 12-29-2008, 06:56 AM   #105
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Originally Posted by Danny/SMC View Post
If it were up to me I would rather everyone in every class runs sub-c cells that way we would be selling allot more packs and our profit margins would be higher.

The fact of the matter is sub-c cells are on the way out and we decided to offer an alternative. We have 3500.00 invested in this pack and the reason we did it is we beleive this will be a good solution. If we wrong we lost 3500.00 and we tried to be part of the solution. If it works out the investment we made will repay itself.
I agree that nickel-based cell technology IS on the way out, and believe it or not I applaud you for taking the initiative and trying to be part of the solution instead of just trying to keep NIMH around for as long as possible.

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Just because I don't personally race 12th scale doesn't mean I don't know and understand what can and can't help this class. After all it's still RC car racing and some of the issues in racing will always be the same.
Some of the issues will be the same, no argument, but there are differences between the classes that make each unique... what works for F1 won't necessarily work for NASCAR... and what works for touring doesn't necessarily work for 1/12.

I'm sorry if I came off as just being argumentative earlier, but while I do recognize that 3.7 LiPO will probably shake out as the future of 1/12 scale, I don't think forcing everyone into the same mold with the 3.7 "brick" format is the right way to help the transition. From what I've seen of loose LiPo's of roughly 2000mah capacity, the saddle pack arrangement may not be do-able because the individual cells are too long to go into a saddle arrangement... ini your "brick" case, are the cells side by side, or are they stacked atop each other? If they're stacked, then they don't lend themselves to a saddle arrangement at all. I don't doubt that it would be possible to get cells built to the size necessary for a saddle, but I don't know if anyone is making such cells now.

I'll tell you this though... I've seen a t-bar car with the brick on one side and all the electronics on the other. I thought it was uglier than a bucket of assholes... I'd sooner design my own chassis or source cells to make my own saddle packs than run a t-bar car like that. I know you don't think the t-bar car is viable anymore, but I'd bet you'd be surprised at how many t-bar cars are still out there. You'd be making the transition a LOT easier if there was some way to get a 3.7 saddle pack into the pipeline.
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