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Old 12-28-2004, 10:58 AM   #61
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The spokes are still out there, just not the billion spoke rim that was the first to come out. I think its a 5 or 6 split spoke design on black, yellow, or white rims. I've ran the yellow ones on my Mi2 at the Hitec race in fact.

Last touring tire developed by Losi and Proline: Yellow 24mm compound slicks from Losi, and the H13 tire that was designed to be a long lasting control tire.
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Old 12-28-2004, 11:06 AM   #62
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I agree with kufman! Increase voltage, NOT decrease. Reducing cell count will putmore demand on the cells. Meaning you will have to purchase the TOP of the mached heap to be competetive. 4 cell packs cost MORE than a 6 cell pack! I am not talking oval here.. they are allways stuck with having to buy the highest run-time numbers. In road course and off-road mod you can buy batteries with good voltage & low internal resistance but don't need the highest run-time numbers. That would change when you lop-off a couple cells. I was racing for Schumacher when ROAR went to 6 cell. 4wd off-road was my class of choice. Prior to the rule change, I ran 7 cells with a mild mod (12 - 15 depending on track size). I could gear it concervitavely and NOT be disadvantaged against anyone! Long motor life and lot's of speed & power. After the switch to 6 cells, I had to run 8-10 turn motors to get the same performance (actually could not quite match previous levels). To make matters worse, Schumacher had recently went to a 2.0:1 internal, making it impossible to properly gear a low wind motor. I had to cut comms every run and still toasted the motors in short order.
Reducing the cell count (lower voltage) puts far more demand on the batteries and motor. This results in higher costs for the privateer! Furthermore, you will likely have to run a receiver pack to keep enough voltage in the receiver. On top of that, many of the cars today (on and off-road) are designed to run 6 cells on one side of the car w/ all electronics on the other, to get proper balance. I realize we can shift stuff over to compensate, but why bother?
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Old 12-28-2004, 11:25 AM   #63
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Fine some pro guys drove the cars with four cell , IF YOU THINK WE HAVE A PROBLEM WITH PEOPLE BUYING BATTERIES FOR VOLTAGE NOW WAIT TILL THEN! [/B][/QUOTE]

I stated that earlier I also ran back in the days when it was seven cell I remember guys paying top dollar to get high voltage cells.
All this is! is a monster waiting to bite us in the as$ .
I uderstand stock would be replaced by 19t but your still going to be paying high dollars for those xtra hi voltage packs.
People the battery problem will be worse.
Oval guys dont have a big problem because they are at or near top end all the time. The europeans and japanese for the most part run on large open and flowing tracks. It may be only 2 tenths slower for them but on tight tracks when you use throttle to get away from the corner and around people it will be like 1 second slowwer.
I mean think about and list all the positive versus the negatives. Is this really the smart thing to do.

The japenese tend to do things like this before anyone else. they have been toying around with eight minute races and seems to be catching on strong there. Dont you think they woulod have tried it already in competition already if it was agood Idea!

We do this hobby for fun the speed is the part of the rush. Why would you take out part of the fun that is why we love racing.
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Old 12-28-2004, 11:26 AM   #64
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v=ir

voltage is linearly directly proportional to current, not inversely proportional. as voltage decreases, so does current, given a fixed resistance. the whole point is that we won't be demanding ,or outputing, the same power #, so an argument based on holding power fixed is not valid here.

c'mon now, brainpower.

eg - for the layfolks... examine how is current related to voltage when you break in your motors. see above for why.
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Old 12-28-2004, 11:27 AM   #65
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Quote:
Originally posted by RC Driver Gary
JKA, you just validified one of my other points
Validified? lol You are right... I did indicate a growth in 12th just like you said. The issue is that you were using this as a justification for TC going to 4cell. I don't really agree. If we have more runtime available we need to lengthen TC races to 8 minutes just like 12th, as I feel its NOT the expense thats appealing but rather the track time.


How about this approach? I hate stock motors. They were intended to level the playing field and be an entry level class, however they've made the most seasoned motor tuner dominant and made dyno's a necessity. How about completely eliminating stock racing and in place of it implementing 4cell?

All motors would be mods thus making the transition from one class to the next much less expensive since only batteries will change. The most problematic issue with mod racing is not the top speed but rather the acceleration which would be minimized with 4cell thus making the cars easier to drive and as such a nice entry level or learning class. Plus rules development and enforcement would be significantly easier.

You get the best of both worlds. The pros and big time drivers still have the blistering acceleration and speed, while the other class can still use all of the same components as the big dogs, but with 2 less cells and thus more control.

Maybe?
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Old 12-28-2004, 11:36 AM   #66
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Default fear?

what is the next level that cell selection will be taken to? and why are we afraid of it? aren't we already doing everything in our power to match and obtain the best cells? by cutting the pack size down 33%, we are also creating exactly 33% more "good" packs to buy out of any given lot. i am surely missing something.
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Old 12-28-2004, 11:38 AM   #67
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Quote:
Originally posted by seaball
v=ir

voltage is linearly directly proportional to current, not inversely proportional. as voltage decreases, so does current, given a fixed resistance. the whole point is that we won't be demanding ,or outputing, the same power #, so an argument based on holding power fixed is not valid here.

c'mon now, brainpower.

eg - for the layfolks... examine how is current related to voltage when you break in your motors. see above for why.
There's a reason why your dryer and larger appliances run off 220volts and why they use 220 volts in europe. Based off amp draw higher voltage uses less amps.
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Old 12-28-2004, 11:40 AM   #68
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yes, but that is designed into the end product. what would happen if you used the same motor/unit with a 110 volt supply?
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Old 12-28-2004, 11:41 AM   #69
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Default Re: fear?

Quote:
Originally posted by seaball
what is the next level that cell selection will be taken to? and why are we afraid of it? aren't we already doing everything in our power to match and obtain the best cells? by cutting the pack size down 33%, we are also creating exactly 33% more "good" packs to buy out of any given lot. i am surely missing something.
Well...crunching the numbers... actually that would be 50% more good packs if you go from 6 cell to 4 cell.

Quote:
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c'mon now, brainpower.
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Old 12-28-2004, 11:46 AM   #70
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damnit. i should have known i was not up for this.
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Old 12-28-2004, 11:47 AM   #71
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Quote:
Originally posted by seaball
damnit. i should have known i was not up for this.
But it does support your point 17% more!
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Old 12-28-2004, 11:48 AM   #72
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I think locally we are probably going to try it.

I put a poll up in our regional forum and it looks like we got at least 4 guys interested...3 makes a class at our local raceway.

Nothing ventured, nothing gained...I run a 12th scale car so I already have the batteries to try it.

Why not? Let's see what happens...
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Old 12-28-2004, 11:49 AM   #73
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man, I gotta take off my shoes to keep up with all this math. Just no trig please
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Old 12-28-2004, 11:57 AM   #74
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Quote:
voltage is linearly directly proportional to current, not inversely proportional. as voltage decreases, so does current, given a fixed resistance. the whole point is that we won't be demanding ,or outputing, the same power #, so an argument based on holding power fixed is not valid here.

Ummm who cares. Power = Current times Voltage.

Losses equal Current Squared times Resistance.

If we double voltage, and cut current in half, the losses go down by a factor of 4!!

A fixed power argument is exactely what we are looking at. you can run 4 cells and a 6000 rpm/v (8 turn ish) motor or 8 cells and a 3000 rpm/v motor (17 turn ish) and get about the same performance. the problem with drawing double the current is that you fry motors faster, have to use bigger wires, have to use more expensive FET's in ESC's and batteries need to have low IR. so yes, if you double the number of cells and keep the same motor, you will draw more current not less, but that isn't the point. The point is to use slower motors with more cells to make a more efficient system.

Hey Gary, if you want trig I am sure I can apply that here too!!
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Old 12-28-2004, 12:00 PM   #75
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Quote:
Originally posted by seaball
yes, but that is designed into the end product. what would happen if you used the same motor/unit with a 110 volt supply?
Is it the amp draw or the voltage that kills motors? from my understanding it seem everybody says amps, right. The reason why you can't plug a 110v device into 220 is that it's multiple phase power. You realize that the power in your wall is a range and not a fixed voltage.

Oh and XRC squared divided by 2 time pie equals hot chicks racing. That's the problem we need more girls at the tracks and you'll see racing be back on the rise. Screw more cells...more silicone!!!!
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