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Old 09-03-2008, 10:51 PM   #16
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Originally Posted by Dondor View Post
look at the vintage class rules.. they are using a combined 4 cell / lipo running and that determines what motor you can use. I am unsure of how competitive it is, but you might try their thread and ask.
The three powertrain options in USVTA are generally very competitive with each other. They are 21.5/lipo, 27T/4-cell, and 17.5/4-cell. There is an FDR limit of 4.2 for the 21.5/lipo option. That being said, powertrain parity is the least of your problems, as others have indicated. Making the larger 7.4 lipo packs work within existing 12th scale framework, from both a weight and size standpoint, will be the challenge.

I resisted this a bunch in USVTA, then manned up and realized how easy it was to break two of my 6-cell stick packs up into three 4-cell packs.
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Old 09-04-2008, 07:22 AM   #17
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All the pro-LiPo posts are from people who have never done it. Please, go and do it and then come back and tell us it is competitive. Those who have done it have not carried on with LiPo in 12th.

Learn from other people's mistakes, you are not going to live long enough to make them all yourself.
There's a growing number of people that don't care if they aren't as compeditive with LiPo compared to NiMh. As one of the guys that has run LiPo in 12th I can say that nothing that we do is going to make them all run the same with different batteries. But, there are more and more people that don't care if their cars are slower than "the fast guys" and they just want to race.

The whole "classic" or "Trans AM" class is great for touring. Setting a gear ratio limit on a foam tire class just won't work. $500+ sedans in a "budget class" never made sense to me either.
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Old 09-04-2008, 01:12 PM   #18
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There's a growing number of people that don't care if they aren't as compeditive with LiPo compared to NiMh. As one of the guys that has run LiPo in 12th I can say that nothing that we do is going to make them all run the same with different batteries. But, there are more and more people that don't care if their cars are slower than "the fast guys" and they just want to race.

The whole "classic" or "Trans AM" class is great for touring. Setting a gear ratio limit on a foam tire class just won't work. $500+ sedans in a "budget class" never made sense to me either.
Agreed, but I've never met anyone who stays in a class where they can't get the cars to handle properly, and every race is a fight. That's usually a signal to go try another class.

I have the same kit as the fast guys, and they are very generous with their set-ups. I just can't drive that well, but every race is fun and I really enjoy it when I drive well and get in the top 30. I am not as good as the fast guys, and I just want to race, but I don't want to fight the car all the time because the kit isn't what's needed for a fast car.

Agree with your comments about cost-controlled classes and 'artificial' limits - I've never seen them work in 30 years of racing!
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Old 09-04-2008, 02:15 PM   #19
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Lipo single cell handles fine in 12th as long as you add weight to make it legal. It's not a big deal.
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Old 09-04-2008, 04:13 PM   #20
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Originally Posted by SlowerOne View Post
All the pro-LiPo posts are from people who have never done it. Please, go and do it and then come back and tell us it is competitive. Those who have done it have not carried on with LiPo in 12th.

Learn from other people's mistakes, you are not going to live long enough to make them all yourself.
Don't care if I'm competitive with, slower than, or faster than 17.5/4 cell nimh 1/12th cars. I predict that within a year, 1S lipo will be the standard battery for any class using 4 cell nimh (especially classes that can't fit a 2S full sized lipo in the car). Fewer and fewer companies are matching and selling nimh batteries, and its only going to get harder to find top quality killer voltage nimh cells.
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Old 09-04-2008, 10:41 PM   #21
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a point towards lipo in 1/12th. I was the guy that the original post was about. I never actually said that I would use the 4900 2S Lipo packs, rather I was headed towards a 2100 2S Lipo. Much different in size. I do understand the weighting issue.. and yep, it's not difficult to add weight in appropriate places. I do also have A123 cells that I could try in a 2S configuration. The car is an associated 12R5.

What really peeves me about NiMh is the battery management that is required at the track. Once you have raced a meeting and have enough LiPo packs to ensure NO charging is required on the day... man what a difference that makes.

I am totally into making life as easy as possible for myself. Race prep is done at home... batteries charged at home.. plug em in and away you go. We are not pushing the larger packs hard at all, so pre-heating is not necessary.

Anyway... continue with the interesting discussion guys...
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Old 09-04-2008, 11:24 PM   #22
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Originally Posted by SlowerOne View Post
All the pro-LiPo posts are from people who have never done it. Please, go and do it and then come back and tell us it is competitive. Those who have done it have not carried on with LiPo in 12th.

Learn from other people's mistakes, you are not going to live long enough to make them all yourself.
I've done it . . .

and I liked it : )
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Old 09-04-2008, 11:50 PM   #23
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What really peeves me about NiMh is the battery management that is required at the track. Once you have raced a meeting and have enough LiPo packs to ensure NO charging is required on the day... man what a difference that makes.

I am totally into making life as easy as possible for myself. Race prep is done at home... batteries charged at home.. plug em in and away you go. We are not pushing the larger packs hard at all, so pre-heating is not necessary.

Anyway... continue with the interesting discussion guys...
I'm totally with you on all of that, but that sentiment is far from universal. I'll probably make some flame-worthy generalizations here, but it's JMO...

There's a certain population of racers who don't see it that way at all. I have found that a goodly chunk of the 12th scalers are included. It takes years to truly master all of the off-track technical skills one needs to be successful in 12th scale. Brushed motor maintenance, battery maintenance, foam tire selection/truing/saucing/rollout change compensation, etc. Many of these racers take a lot of pride in their mastery of those subjects (and rightfully so) and see those who aren't as excited about those topics as lazy or ignorant or unsophisticated. Then brushless motors come along and take one element away. Grumble, grumble, but life goes on. Now lipo is in the works and attitudes are getting ugly. I had the nerve in another thread to ask about (gasp!) rubber tires on pan cars and was nailed to a cross. I was told in no uncertain terms that if I wanted brushless, lipo, and rubber in a pan car then I should just stay home and play a video game.

I actually love all of the technical aspects of RC racing. I'm a mechanical engineer and my brain is just wired that way. I love obsessing over the details building and maintaining my cars, being anal about setup, and making spreadsheets of changes and the results for analysis. It's just that I love to do these things at home in the evenings in the garage with a six-pack. When I'm at the track I want to race and have fun! I guess that makes me lazy.

I don't know about the rubber tires, but you're a fool if you don't believe that within a couple of years brushless/lipo will dominate 12th scale. Why wouldn't it? People can be so resistant to change.

The funny thing is how people are so quick to yell that it'll never work. Sure, if you take a pan car designed around brushed motor architecture and 4-cell power and try to just slap in a brushless/lipo combo it won't work for squat. But when you cleverly compensate for the differences in the interim, and then industry responds and designs a car around it, it's a whole different ballgame.

If you took a touring car all set up for 6-cell brushed and dropped in a brushless/lipo kit, it would be just as ill-handling and poorly-geared as doing the same in a pan car. Touring cars obviously compensated, and now it's the norm. Impossible!

Bleh. Just my .02. Crucify me again if you will, but then I'm going to dig this thread back up in a few years and say "I told you so!"
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Old 09-05-2008, 01:24 AM   #24
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lol reenmachine....

my problem is that I don't only race cars. I fly model helis/planes and also race nitro/electric and petrol boats. So whilst I appreciate the skills that some of the guys have with regard to setup/maintenance etc.. it's just another area that I want to spend the minimum time on. Cars for me are fun, and sharpen my driving skills. My main passion is the boat racing.

I AM one of the lazy ones that totally welcomes to coming of brushless motors and LiPo packs... Plus it means that you can be more social at a race meeting, chatting with people etc.. rather than being head down working on your car all the time. It also means that people will have more time to help actually run the meets... something that seems to be somewhat lacking at the moment (participation by more than the currently devoted few).
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Old 09-05-2008, 05:46 AM   #25
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I never actually said that I would use the 4900 2S Lipo packs, rather I was headed towards a 2100 2S Lipo.
From the testing that I did, it's likely that you will dump a 2100 2S lipo in 8 minutes even with a 21.5 motor or something like that. Now, if you take that 2100 apart and wire it as a single cell pack (4200) you won't dump in a stock type class.

Requires a gear change to keep up and it will be a little slower on the straight but definately a lot less work.
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Old 09-05-2008, 06:13 AM   #26
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FredB...

At this stage, for club level racing, we are running 5 min heats. I am guessing that with the very mild setup I am planning, run time and battery damage should not be an issue.

Higher level racing, I leave to the experts to sort out...
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Old 09-05-2008, 06:28 AM   #27
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what about that single cell lipo thats out (with a rx pack of course)?

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Old 09-05-2008, 07:14 AM   #28
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There's a key difference I've just realised. In the US, you basically don't do Modified motors in any pan class. In Europe, we do it all the time. I'm comparing a class in the US where you run 17.5 and 13.5, with a class in Europe where we run 10.5BL and Mod (6.5 to 4.5BL).

On a personal note, I like NiMh, I have no trouble looking after my current packs, and I don't want to go LiPo. I don't like posts that tell me I am somehow a lesser being for not changing. The future isn't LiPo anyway, the future is A123, so why invest in a technology that will be out of date in three years when I already have all the kit I need to compete? Instead of asking me to accept that I have to go LiPo, it would be nice to hear someone say that both could exist together.

We couldn't compensate for a single-cell LiPo with motors, as they just wouldn't be competitive - where do you go if you're already running a 4.5 to find power that competes? Also, for the majority that run 10.5BL, we don't want to get involved in receiver packs, chargers, the additional weight and the complication - they're not needed with 4.8v. We find the latest EP and EnerG cells easy to come by, and we have the Orion SHO cells (a European spec, essentially a 3700 cell) behave just like your LiPos - charge, race, store; charge, race, store...

On top of that, here, we now have matched LiPos, secret overcharging of LiPo, and LiPo warmers. All of these would be a great benefit to a single-cell LiPo class as the difference in voltage would be significant and valuable.

I'm not against LiPo, I am against pretending that to make a 12th car go, all you have to do is bolt in a LiPo and change the motor. These little critters are sensitive enough as it is! If you want single-cell LiPo, do what Fred B says and add weight - oh, and don't forget the receiver pack, charger, to charge it before every other run...

Back on topic directly, there is no equivalence between NiMh and LiPo in 12th. If people want to run it I suggest they take a leaf out of Scotty's book - write some Rules and everyone develop to those Rules. Scotty did this with WorldGT at the IIC, and his Rules are about to be considered for racing in Europe - we all agree they work and can be used as a basis for development. IF you could all agree that the Rules were (say) single-cell LiPo with 10.5 motors, then at least you could get on with it!
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Old 09-05-2008, 08:15 AM   #29
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Originally Posted by SlowerOne View Post
On a personal note, I like NiMh, I have no trouble looking after my current packs, and I don't want to go LiPo. I don't like posts that tell me I am somehow a lesser being for not changing. The future isn't LiPo anyway, the future is A123, so why invest in a technology that will be out of date in three years when I already have all the kit I need to compete? Instead of asking me to accept that I have to go LiPo, it would be nice to hear someone say that both could exist together.
I certainly don't think you're a lesser being for not changing and I apologize if I came off that way. Both can exist together -- it'll just be much harder with 12th scale to make them do so in the same class like we do with touring cars.

Battery technology is changing (advancing?) very quickly in the world today since every damn thing is electronic. RC is just a tiny consumer of battery products behind the mass-market electronics that drive the technology. Basically, that means we'll have to use whatever everyone else is using. That will mean the virtual disappearance of NiMh before too long.

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If you want single-cell LiPo, do what Fred B says and add weight - oh, and don't forget the receiver pack, charger, to charge it before every other run...
Ummmm...you defend fiddling with NiMh in one sentence and then goof on receiver packs in another? What's the big deal about receiver packs? There are a million good options on the market and the 4 bazillion nitro guys don't seem to have a problem with them...
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Old 09-05-2008, 08:20 AM   #30
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I ran a 3.5 when I was looking at single cell LiPo. It's pretty fast but drives different than NiMh with a 4.5 turn. Even at legal weight.

I agree that the new NiMh cells are way better than what we had about a year ago. Much less maintenance and they're lasting longer. That being said, I'll be trying more LiPo stuff this winter.

Changes to the classes will come as people try new things at the club level. Not so much from the big races.
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