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Old 03-19-2010, 10:59 PM   #13426
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Originally Posted by Krio View Post
I'll finish this comment later, but for the last time stop saying the load has an impact on torque. Its grammatically, mathematically, and physically not correct.
Thank you. I will wait.

That should be gramatically though.
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Old 03-19-2010, 11:11 PM   #13427
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I'll finish this comment later, but for the last time stop saying the load has an impact on torque. Its grammatically, mathematically, and physically not correct.
But, "its" should be "it's"; plus, a few other punctuation errors. Sooooooooo there!
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Old 03-20-2010, 12:10 AM   #13428
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Originally Posted by niznai View Post
Thank you. I will wait.

That should be gramatically though.
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Originally Posted by Still Bill View Post
But, "its" should be "it's"; plus, a few other punctuation errors. Sooooooooo there!
All hail the translation of sarcasm on the internet!

Quote:
Originally Posted by niznai View Post
Absolutely. That's why I want such a map.

That line actually begins with a very abrupt (almost instant) rise from zero to maximum. I am talking in a torque vs RPM space. After reaching the peak, it descends as RPM increase. This is where the fun starts as theory predicts the line descends, oh well, like a line, in a linear fashion (duh). Reality is different, but theory needs a lot of data to predict exactly what happens.

Ok, so were on the same page there then.

And indeed efficiency (and load too, I am sure) has an impact on torque, that's why I bang on and get all sorts of people saying all sorts of things. I have no proof other than basic physics principles. Real torque curves for electric motors support my statements (as well as my personal experience) however.

Full throttle = 7.4 volts. I'm not sure what you mean by "load", but the "load" has no impact on torque output. When you grab full throttle the motor is putting out full torque for that given rpm no matter what else his happening. If the "load" is less than the output of the motor than the excess torque is used to accelerate the car; all the while the motor is putting out full torque at each given rpm. For us the primary load is the mass of the car accelerating.

Form this point moving on to variable timing motors I am sure things get a lot more complicated, but I have never seen any data on this. I agree this is best presented in a 3d space, but I would settle for a combination of two relevant 2d diagrams.

Things really don't get any more complicated. It becomes more labor intensive to produce the same graph if you are optimizing the timing for every rpm, but in short the line just gets "pooched" out. I have attached a graph I painstakingly hand drew when trying to explain optimum timing for any given rpm earlier in this thread when many people were all "more timing only means more rpm".

About power, I believe so too. But before someone with the resources takes on the task of investigating these ideas and produce the diagrams we will not have the power to use the technology to its full potential.

I may not have access to the graphs anymore, but I was working on a hybrid semi truck project last year (before it was scrapped along with the economy) and was helping with dyno testing the massive brushless motors and cycling lithium battery packs with 20C charge rates. The idea was to eliminate the norm of truckers idling their engines all night to power their ac and mini fridges. This was to be achieved by fast charging the packs from 30 percent state of charge (soc) to 70 percent soc by turning the engine on for only 5 minutes every hour. We may or may not have smoked some hitachi battery packs...
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Old 03-20-2010, 03:28 AM   #13429
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Hi Krio,

Do you have any references to articles (on the web maybe?) along the lines of your quite interesting discussion ??

Thanks in advance
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Old 03-20-2010, 05:52 AM   #13430
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Default tekin brakes

there seem to be a lot of talk about the lack of brake the tekin has .i have just bought a tekin rs pro love the power of this esc.but i have to agree that the brakes compared to a spx lrp are no wear near as good .is there any thing you can do other than full brake on the radio and esc . thanks

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Old 03-20-2010, 07:18 AM   #13431
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Turn your breaks down

they work better when they don't lockup
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Old 03-20-2010, 07:49 AM   #13432
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I took my T3 outside and we have a HUGE 70m straight , t the end of the straight i was braking and it seamed like it was not braking , I put this down to the extra straight line speed compared to last years speeds

But thinking about it for a few days i think they are not so good , I have only tryied the car for one day outside on a long straight so some more testing is required .

I tried 100% on the speedo and on the transmitter , Also tried turning the transmitter and the speedo brakes down but still no better

I am also 100% that the wheels were not locking up
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Old 03-20-2010, 07:58 AM   #13433
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For those of you with braking issues, could you please list your settings, motors, chassis, gearing, transmitter, etc.

fwiw, the brakes with my RS on 12th, F1 & Touring have been more than enough. I have noticed though, the more esc timing the stronger they are.
v203 brakes are the best yet on the RS.
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Old 03-20-2010, 08:15 AM   #13434
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Nice post Krio...Kewl thoughts!
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Old 03-20-2010, 08:32 AM   #13435
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Originally Posted by RedBullFiXX View Post
For those of you with braking issues, could you please list your settings, motors, chassis, gearing, transmitter, etc.

fwiw, the brakes with my RS on 12th, F1 & Touring have been more than enough. I have noticed though, the more esc timing the stronger they are.
v203 brakes are the best yet on the RS.
i am running 50 timing and 4-8 turbo with duo1 motors in 1s 1/12 and the brakes are too much. I actually have to bump down the brakes to <70 or the car locks up. this is both 17.5 and 13.5 and rollout is 90-92mm in 17.5 and 82-85mm in 13.5. radio is the helios with ko2.4
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Old 03-20-2010, 08:43 AM   #13436
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i am running 50 timing and 4-8 turbo with duo1 motors in 1s 1/12 and the brakes are too much. I actually have to bump down the brakes to <70 or the car locks up. this is both 17.5 and 13.5 and rollout is 90-92mm in 17.5 and 82-85mm in 13.5. radio is the helios with ko2.4
Yeah whan i was indoors the brakes were great

It just seams that when the speeds are really high then they suffer a little

I am running about 50 timing and max turbo , using the Tekin 13.5 motor 2S in an Xray T3

Gearing of 5.5
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Old 03-20-2010, 09:08 AM   #13437
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Quote:
Originally Posted by b33 View Post
there seem to be a lot of talk about the lack of brake the tekin has .i have just bought a tekin rs pro love the power of this esc.but i have to agree that the brakes compared to a spx lrp are no wear near as good .is there any thing you can do other than full brake on the radio and esc . thanks
Quote:
Originally Posted by sidecarphil1 View Post
I took my T3 outside and we have a HUGE 70m straight , t the end of the straight i was braking and it seamed like it was not braking , I put this down to the extra straight line speed compared to last years speeds

But thinking about it for a few days i think they are not so good , I have only tryied the car for one day outside on a long straight so some more testing is required .

I tried 100% on the speedo and on the transmitter , Also tried turning the transmitter and the speedo brakes down but still no better

I am also 100% that the wheels were not locking up
I found that using 80% brakes was slightly better for the high speed braking, although it did mean you lost a little at the slower speeds.

Will be trying somesettings out again tomorrow.

x12 10.5 (standard timing)
v203
40 timing
10 turbo
0.5s
2.0 ramp
100 down to 80% brake
10 neutral
no drag brake (but have used a little lately indoors to help balance the car into corners.)

Skiddins


Indoors the brakes are great because the cars aren't as fast so they are more effective.
P.S. have tried all the EPA adjustments and tips n tricks etc for the radio to get better brakes, none of that stuff worked.
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Old 03-20-2010, 09:11 AM   #13438
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I can't imagine not having enough brake with the RS. I run 100% on the speedo and 55% on my radio and I still have more than enough brake. I ran about the same on my SPX, maybe a little less on the radio.
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Old 03-20-2010, 09:22 AM   #13439
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Default For what it is worth...

I ran two versions of firmware before 203. All had lackluster brakes. I just upgraded to 203, left my 200 setting, guessed at an RPM range from setups on the Tekin site, and -POOF- I had brakes. I think I even turned the brakes down to 80 and they still feel good.
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Old 03-20-2010, 09:24 AM   #13440
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Default not enough brakes?......try a new motor

I too also was struggling for brakes. Then I put a new motor in, sp17.5 version2, which replaced the same old motor, and now I have brakes

before, the wheels wouldnt even lock up, but now I need to set my TX epa to 80%

would not think a new motor would have such an effect. I guess the rotor of brushless motors loose their magnetism over time, however you cannot feel the difference when free spinning the motors by hand.
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