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Old 01-04-2008, 01:00 PM   #331
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The 26650 cells are close to a standard "C" size and have less capacity than a NiMh cell. They aren't bad cells but they won't drop into many cars and certainly not 12th.
You can easily fit four(4) 26650 cells into a 1:12 saddle pack t-bar car. The slots are already cut for 65mm long for front/rear weigt bias. It would reqire the slots to be slightly wider apart since Sub-C are smaller diameter.

What I foresee in 1:12 would be using only Two(2) 26650 cells to limit capacity in the future and still have a configuration for linked cars. In time when LiPO's get better and trend seems to be that 26650 cells will top off near the 4000 to 4400mah range in LiPo, and 3500 in LiFePO4. There would be no point to taping in an 8000mah battery into 1:12 cars unless you were running enduro. The limit in capacity would help keep the speeds down in 1:12 modified but not really so much in stock. Right now LiPO 26650 cells suck and can not really take the abuse as LiFePO4 cells which A123 I feel makes the best in that chemistry. When LiPo's get better, the switch can be made to higher capacity and volatge should it be needed to improve racing.
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Old 01-04-2008, 01:06 PM   #332
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I'm with "Slappy" on this. I've done similar testing with smaller BL motors, and I'm positive Cyrul has too. It makes a HUGE amount of sense. I'm more of a higher voltage kind of guy too. And if Lipo were to be a logical path for 1/12th, then let's up the voltage. Less radio drop outs, easier power. Potentially longer races, lighter car=less damage. Lot's of positives.
I favor the lighter 1:12 cars: Smaller batteries, smaller motors add up to fatter wallets.
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Old 01-04-2008, 01:59 PM   #333
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You can easily fit four(4) 26650 cells into a 1:12 saddle pack t-bar car. The slots are already cut for 65mm long for front/rear weigt bias. It would reqire the slots to be slightly wider apart since Sub-C are smaller diameter.
The A123 cells do not fit in my 12th. The diameter is also too large to fit a body on the car. The battery slots on my CEFX car (and a 12L etc) are cut for a 43mm long sub C cell.

the 26650 cells are 3mm larger diameter and 21mm longer. They just plain won't fit into a 12th roadcourse car. Not Gonna Happen.
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Old 01-04-2008, 02:35 PM   #334
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Remember we ran 6 cell stock 1/12th outdoors for many years. So if they could fit then then there should be ways to make a LiPo fit. On top of that if you reduce the motor down to a 380 sized motor the motor pod will get a lot smaller which will give you more room to extend the chassis for even more room for the larger battery.
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Old 01-04-2008, 02:38 PM   #335
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Some people from A123 came to our track a while back to do some 'testing'. I don't know what they were testing, as I never seen them take out anything to test with.

It was at that time that they showed me their cells and asked what I thought of them. At that time (about 2 years ago) I told them that if the cells can conform to the space engineered within the current models they would stand a better chance to get racers to adopt their batteries, this due to the current manufacturers making chassis to conform to the current legal batteries.

About a year later, they returned and we talked once again about interest in their concoction of LiPo, to which I pushed the discussion back to the form factor of the cells and how they would need to change to that to get early adopter racers to buy into their tech.

I wasn't trying to discourage them from coming out with a new technology. The big problem that was evident was convincing some 20 or so manufactures that they needed to change the design of their chassis because there was one new battery company on the block that wanted to make inroads into the hobby. I really don't think that the two 'engineers' that came to our track to do testing ever took that advice to heart. I still see their cells around in the same form factor.
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Old 01-04-2008, 02:49 PM   #336
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yea...

chicken and egg... good comparison..
First I want to say, Dawn, you are doing an awesome job!!! I have been a ROAR member since 1980 and this is the first time during my membership, that a ROAR President has been so readily accessible and responsive.

I race 1/12th road racing 99.9% of the time. I occasionally will run oval. So I will only put in my 2 cents regarding brushless rules for 1/12th. (Yes, you can have different formulas/rules for different classes)

A good 17.5 brushless motor can beat a good brushed 27T motor. I have witnessed this a couple of times. A 13.5 brushless will blow the doors off of the best 27T motor you can find. There is just no comparison.

A good 10.5 brushless is very close to a good brushed 19T but right now, a very strong, hand picked, blue printed brushed 19T is still faster than a 10.5. Not by much though and I think that once the 10.5 has more hours under its belt, it will be equal. So…

As far as rules for 1/12th it should be as follows:

Stock = 17.5 brushless or 27T brushed. Leave it up to each individual racer as to which motor/system they want to run.

19T = 10.5 brushless or 19T brushed. Leave it up to each individual racer as to which motor/system they want to run.

Now the above rule does leave 13.5 out of the 1/12th formula but for those racers using 13.5 in 1/12th, you can sell them to one of the other classes that do end up with a 13.5 in their rules.

As far as batteries, there are no lipos currently available to support the existing 1/12th formula. Asking the manufactures to change the design of the current formula in one year is not realistic. For the foreseeable future, 1/12th will be stuck with four sub C batteries. In time, car design will change and lipos will be manufactured that will support 1/12th. Also, with the knowledge learned from the use of lipos in other formulas, a better understanding of the direction 1/12th should take will be better understood and new rules can be drafted at that time.

Rick Hohwart posted that the class names should be changed back to what they where in past.

Stock = Sportsman.

I support this 100%. This would [I]minimize[/I] the upper level drivers entering stock. It would not totally eliminate it but any upper level driver that drops down into the “Sportsman” class would definitely draw unwanted attention to themselves. There could also be criteria set that would define Sportsman such as “0” ROAR Regional A main wins or equivalent.
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Old 01-04-2008, 02:52 PM   #337
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The A123 cells do not fit in my 12th. The diameter is also too large to fit a body on the car. The battery slots on my CEFX car (and a 12L etc) are cut for a 43mm long sub C cell.

the 26650 cells are 3mm larger diameter and 21mm longer. They just plain won't fit into a 12th roadcourse car. Not Gonna Happen.

26650 is the SIZE ~26 x 65.xx mm. the only cars they have a chance fiting into current slots are front to back if you arent interfering with the shock.. and side to side slots will not work whatsoever unless you like a chassis that doesnt hold its shape lol. The other issue is not all of us seem to be talking about the same thing. A123's lithium phosphate (and whatever else is in there) is 3.3v. add two together and you're at 6.6v - Not the 7.4 we're talking.

I dont know if the ROAR Committees have kept all the possible lithium combos on a list to keep track of. They may only be looking at one or two types of chemistry. And now many people are really wishing they paid more attention back in high school chemistry class.
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Old 01-04-2008, 03:01 PM   #338
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if a lipo fit my slider tray in my oval car and was alot closer to 4.8 volts i would throw away all nimh stuff in a heart beat...the 12th on-road guys have the same problem i do...


oval needs 4 classes

17.5 stock
13.5 sportsman
10.5 19 turn
open mod

that formula does not work with lipo's..... and i wouldn't even try to compare any brushless motor with any brushed motor.......phase them out in oval every brushless motor is better on the track than it's so called brushed counter part.
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Old 01-04-2008, 03:33 PM   #339
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I really don't understand the hatred some of the racers show towards brushed motors. If they are so bad, let them die on there own my being unused, let the racers decide what works for them. But to just come out and delete all those that chose to run with that technology, just seems wrong, and I hope ROAR will take that into consideration. Just because your local club doesn't/won't/can't run them has nothing to do with what ROAR is trying to set for standardized rules.

Why doesn't someone set up a link to a poll and see what the vote would be? (I'm not web smart enough to do it myself)

From what I've read (and have raced) the equivelent structure would be as follows;

17.5/27t
10.5/19t
mod/mod
*all running under the same existing weight rules.

As far as batteries go, make the LiPo people go back and configure a pack that will fit what most of our cars where made to except, 2x2, 2x3 or 1x6 cell configurations (sorry no sticks in Nats type racing, as far as I know) You know it can be done, just look at what they do with all the different brands of drills, cell phones, etc. Quit trying to change the chicken, make a better egg. Of course I'm sure we are such a small market share, they'll tell us to get lost, but maybe thats a hint, maybe LiPos' aren't meant for surface vehicles.
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Old 01-04-2008, 03:54 PM   #340
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Originally Posted by Johnny Wishbone View Post
I really don't understand the hatred some of the racers show towards brushed motors. If they are so bad, let them die on there own my being unused, let the racers decide what works for them. But to just come out and delete all those that chose to run with that technology, just seems wrong, and I hope ROAR will take that into consideration. Just because your local club doesn't/won't/can't run them has nothing to do with what ROAR is trying to set for standardized rules.

Why doesn't someone set up a link to a poll and see what the vote would be? (I'm not web smart enough to do it myself)

From what I've read (and have raced) the equivelent structure would be as follows;

17.5/27t
10.5/19t
mod/mod
*all running under the same existing weight rules.

As far as batteries go, make the LiPo people go back and configure a pack that will fit what most of our cars where made to except, 2x2, 2x3 or 1x6 cell configurations (sorry no sticks in Nats type racing, as far as I know) You know it can be done, just look at what they do with all the different brands of drills, cell phones, etc. Quit trying to change the chicken, make a better egg. Of course I'm sure we are such a small market share, they'll tell us to get lost, but maybe thats a hint, maybe LiPos' aren't meant for surface vehicles.
After watching some of the Novak TC race online, it is pretty clear that we need to eliminate the 10.5 class. Eliminating it will allow a decent gap between 13.5 and modified.
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Old 01-04-2008, 04:01 PM   #341
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Eliminate essentially the intermediate point of racing in ROAR ... the 19T class or 10.5 in BL?

where is the stepping stone for the new racer at the club level who's attempting to master stock style of racing with either a 27T or a 17.5 (for arguements sake... don't jump on that as fact yet! LOL) and then all the way up with the guys that are running a 7.5 or 6.5 or 4.5 BL / 11T, 12T or even a 9T?

If we are going to SLOW down stock and bring racing back to the club level it needs to be to generate growth in the sport and yes, of course, I want to generate more membership in ROAR, I feel we need to think about the Joe Racer, newbie and his/her buddies first.

Don't.. please.. don't ask for 19T or the intermediate level of racing to go away. I hate the fact we have TOO many options but now they are there and we can't just zap them off the planet....

Or.. am I misunderstanding what your saying?
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Old 01-04-2008, 04:11 PM   #342
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After watching some of the Novak TC race online, it is pretty clear that we need to eliminate the 10.5 class. Eliminating it will allow a decent gap between 13.5 and modified.
Is this playing into why LRP doesn't make a 10.5 yet? You feel we should eliminate this class.... C'mon Rick!
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Old 01-04-2008, 04:13 PM   #343
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Originally Posted by Dawn Sanchez View Post
Eliminate essentially the intermediate point of racing in ROAR ... the 19T class or 10.5 in BL?

where is the stepping stone for the new racer at the club level who's attempting to master stock style of racing with either a 27T or a 17.5 (for arguements sake... don't jump on that as fact yet! LOL) and then all the way up with the guys that are running a 7.5 or 6.5 or 4.5 BL / 11T, 12T or even a 9T?

If we are going to SLOW down stock and bring racing back to the club level it needs to be to generate growth in the sport and yes, of course, I want to generate more membership in ROAR, I feel we need to think about the Joe Racer, newbie and his/her buddies first.

Don't.. please.. don't ask for 19T or the intermediate level of racing to go away. I hate the fact we have TOO many options but now they are there and we can't just zap them off the planet....

Or.. am I misunderstanding what your saying?
My point is that 19T/10.5 is not an intermediate class. It hard to argue with the fact that when R/C racing was biggest, and there were 20,000 ROAR members, there was no 19T class and there were no rebuildable stocks. There is no way to argue that these two developments helped racing.

17.5 is the stock/entry level/Sportsman class. 13.5 is the intermediate class, and modified BL/brushed is the top class. This is how I would officially structure it.
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Old 01-04-2008, 04:15 PM   #344
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Is this playing into why LRP doesn't make a 10.5 yet? You feel we should eliminate this class.... C'mon Rick!
I have nothing to do with what LRP does or does not develop.
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Old 01-04-2008, 04:18 PM   #345
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Preach it Rick...
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