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Old 05-13-2006, 03:06 AM   #16
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Actually no, it can't be the tray: it works flawlessly (except does not cut off) with my 1900 batteries.
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Old 05-13-2006, 05:16 PM   #17
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make sure you dont run that ib pack dead. it has to have atleast 300 seconds of charge in it after it is done being used. also dont take below .9v per cell.
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Old 05-13-2006, 06:23 PM   #18
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Quote:
I had about 10 minutes of runtime (I have to mention that the trigger was floored most of the time, or I was triving with a twitchy finger). Then the car started stuttering.
If you didn't have any problems to start, that is one of them.

You are just running your car TOO long.
You should limit it to 8 minutes, even if the car still seems like it is running strong.
For one, its really hard on the motor to go that long.
Two, it will eventually ruin your ESC.
(Especially if you run the car untill the battery is dead, because it pulls more and more amps through the ESC, which will cause it to heat up and fail.)
Three, running your batteries at that load for that long will really shorten their life, especially if you have a cell that goes dead before the others do, then it basically is charging that cell in reverse, and its ruined.
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Old 05-14-2006, 02:35 AM   #19
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Quote:
Originally Posted by PitCrew
If you didn't have any problems to start, that is one of them.

You are just running your car TOO long.
You should limit it to 8 minutes, even if the car still seems like it is running strong.
For one, its really hard on the motor to go that long.
Two, it will eventually ruin your ESC.
(Especially if you run the car untill the battery is dead, because it pulls more and more amps through the ESC, which will cause it to heat up and fail.)
Three, running your batteries at that load for that long will really shorten their life, especially if you have a cell that goes dead before the others do, then it basically is charging that cell in reverse, and its ruined.
Well, my Tamiya ran fine for 15 minutes with a Mabuchi motor...

I didn't just buy the car to race, I want to drive around too...

And when I discharge my pack, I put 0.9V/cell cutoff... thats 5.4 volts, and the pack doesn't reach this voltage when running AFAIK
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Old 05-14-2006, 02:52 AM   #20
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dude, just buy some new cells.......
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Old 05-14-2006, 04:43 AM   #21
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Quote:
Originally Posted by whoopass
dude, just buy some new cells.......
I already have... SMC IB3800. Charging 'em now.
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Old 05-14-2006, 08:26 AM   #22
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Well, OK, cells seem to be good. I came home, measured them all, they all show 1.335.

But another thing occured: I was driving, and whoa, smoke comes out of my motor.... the insulation melted inside.
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Old 05-14-2006, 08:33 AM   #23
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Thats what running for 15 minutes will get you. Those IB3800's are better if you don't run them until your car slows. I would advise no more than 10 minutes a run. I run longer, you will just kill the cells.JMO
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Old 05-14-2006, 12:39 PM   #24
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Originally Posted by BeetleBailey
Thats what running for 15 minutes will get you. Those IB3800's are better if you don't run them until your car slows. I would advise no more than 10 minutes a run. I run longer, you will just kill the cells.JMO
The cells are FINE, the motor is DEAD.

Now, could someone explain to me what you use to train? I mean, running my car longer than 15 minutes, what should I use (which motor)?

Don't worry, I'll do my best to stop driving as soon as it feels slower... it gets boring then anyways.
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Old 05-14-2006, 01:10 PM   #25
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Quote:
Originally Posted by D_o_S
Well, my Tamiya ran fine for 15 minutes with a Mabuchi motor...

I didn't just buy the car to race, I want to drive around too...

And when I discharge my pack, I put 0.9V/cell cutoff... thats 5.4 volts, and the pack doesn't reach this voltage when running AFAIK
A mabuchi motor is WEAK, compared to a decent stock motor.
It pulls much less amps, so you will get a much longer run time. For instance, we recently had an enduro race that was 12 hours, using Tamiya mini coopers and mabuchi motors. We consistently got 30 minutes of run on GP3300's, and we ran the same motor the whole 12 hours. My team won. $1000 prize.
But a rebuildable stock motor probably wouldn't have made it the whole time, and we certainly would not have gotten that kind of run time.

And see now you smoked your motor. You are over-running your car.

Don't ask for advice and help to figure out a problem you are having, and when everyone is basically saying the same thing, you are disregarding it.

Don't forget, you can run your car untill it basically stops, and when you take your car inside and measure the voltage across the cells, they are GOING to read much higher, like 1.2 or more. This is called "Rebound" voltage. But the cell can not produce that voltage with any kind of load placed across it.

You need to STOP running your car around the 8-10 minute mark, and let all your stuff cool off. Then discharge the remainder of the battery on your discharge device. And, don't charge your pack again for at least an hour or so. It needs to have cooled off to room temperature. But don't be dumb and put the battery in the fridge or something. Especially don't charge a COLD battery. It will overcharge. Yeah I tried that one. Charged a pack with it in a small fridge. It toasted it.
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Old 05-14-2006, 02:04 PM   #26
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Quote:
Originally Posted by PitCrew
A mabuchi motor is WEAK, compared to a decent stock motor.
It pulls much less amps, so you will get a much longer run time. For instance, we recently had an enduro race that was 12 hours, using Tamiya mini coopers and mabuchi motors. We consistently got 30 minutes of run on GP3300's, and we ran the same motor the whole 12 hours. My team won. $1000 prize.
But a rebuildable stock motor probably wouldn't have made it the whole time, and we certainly would not have gotten that kind of run time.

And see now you smoked your motor. You are over-running your car.

Don't ask for advice and help to figure out a problem you are having, and when everyone is basically saying the same thing, you are disregarding it.

Don't forget, you can run your car untill it basically stops, and when you take your car inside and measure the voltage across the cells, they are GOING to read much higher, like 1.2 or more. This is called "Rebound" voltage. But the cell can not produce that voltage with any kind of load placed across it.

You need to STOP running your car around the 8-10 minute mark, and let all your stuff cool off. Then discharge the remainder of the battery on your discharge device. And, don't charge your pack again for at least an hour or so. It needs to have cooled off to room temperature. But don't be dumb and put the battery in the fridge or something. Especially don't charge a COLD battery. It will overcharge. Yeah I tried that one. Charged a pack with it in a small fridge. It toasted it.
I know there is almost no point in measuring voltage with no load...

You said endurance race... well, what I want to do is race, and drive around... I want to take my car out and just drive, drive, drive... like for an hour or so. I don't want to kill anything, so what would you reccomend?

I just can't imagine everyone getting out, running their car for 15 minutes at a race, and then saying thats it... and becoming champions.

I am convinced that practice makes perfect, and so I would like to practice... If I got a 27x1 motor, or a stock motor, how long could I run that? 30 minutes?

And you say that I shouldn't run the car for more than 10 minutes... well, above you posted that you were in an endurance race, with GP3300s (yeah, OK, IBs might behave differently) and you got 30 minutes of runtime... I imagine you used the same car throughout the race, and didn't say "30 minutes is way over 15, my car/stuff can't handle it anymore, it needs a break". What I'm asking is what I have to do in order to do those sort of things.

I can understand that at a race, I need best performance - I can run aggressive gearing, etc, and have to be careful. But I also want to get out and drive (or bash, as some people would call it). I want to practice. And I want the "practice" stuff to last long. I mean, the past few days have just been horrible (possibly due to my inexperience, but I would blame the motor blowing on a manufacturing defect). You see, I got a T1FK, and top of the grade stuff. Now I imagined that I could do exactly the same as with a Tamiya TT01, and I guess I was wrong. In the past couple of days/weeks, I went out to drive, and my car didn't last me over 20 minutes (and I did do everything according to manuals)... once, the bearings screwed up... the pinion got loose, then batteries went haywire... now the motor. With my tamiya, it was not uncommon that I would go out and drive for 30 or more minutes, with not a single failure.

Let me repeat my question once again: what should I get/do in order to be able to "practice" and drive for fun? Oh yeah, and maybe increasing the drive frequencies with my KO Propo VFS would help....

I admit - I am a n00b.

TIA
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Old 05-14-2006, 02:35 PM   #27
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Or maybe, could I lower the profile and back the EPA on my 3PK? Would that help to get more run time and less wear?
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Old 05-14-2006, 08:16 PM   #28
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Quote:
Originally Posted by D_o_S
You said endurance race... well, what I want to do is race, and drive around... I want to take my car out and just drive, drive, drive... like for an hour or so. I don't want to kill anything, so what would you reccomend?
LiPo and brushless...
-Josh
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Old 05-14-2006, 08:27 PM   #29
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Quote:
Originally Posted by D_o_S
I know there is almost no point in measuring voltage with no load...

You said endurance race... well, what I want to do is race, and drive around... I want to take my car out and just drive, drive, drive... like for an hour or so. I don't want to kill anything, so what would you reccomend?

I just can't imagine everyone getting out, running their car for 15 minutes at a race, and then saying thats it... and becoming champions.

I am convinced that practice makes perfect, and so I would like to practice... If I got a 27x1 motor, or a stock motor, how long could I run that? 30 minutes?

And you say that I shouldn't run the car for more than 10 minutes... well, above you posted that you were in an endurance race, with GP3300s (yeah, OK, IBs might behave differently) and you got 30 minutes of runtime... I imagine you used the same car throughout the race, and didn't say "30 minutes is way over 15, my car/stuff can't handle it anymore, it needs a break". What I'm asking is what I have to do in order to do those sort of things.

I can understand that at a race, I need best performance - I can run aggressive gearing, etc, and have to be careful. But I also want to get out and drive (or bash, as some people would call it). I want to practice. And I want the "practice" stuff to last long. I mean, the past few days have just been horrible (possibly due to my inexperience, but I would blame the motor blowing on a manufacturing defect). You see, I got a T1FK, and top of the grade stuff. Now I imagined that I could do exactly the same as with a Tamiya TT01, and I guess I was wrong. In the past couple of days/weeks, I went out to drive, and my car didn't last me over 20 minutes (and I did do everything according to manuals)... once, the bearings screwed up... the pinion got loose, then batteries went haywire... now the motor. With my tamiya, it was not uncommon that I would go out and drive for 30 or more minutes, with not a single failure.

Let me repeat my question once again: what should I get/do in order to be able to "practice" and drive for fun? Oh yeah, and maybe increasing the drive frequencies with my KO Propo VFS would help....

I admit - I am a n00b.

TIA
If you just want to drive around in the street, or practice for long periods of time, then do this.

Run a mabuchi 540 motor. (don't run a good stock motor for those kinds of time periods)
Run a higher frequency setting on your speed control.
And STOP driving right when you can notice the car is slowing down. That means that one or more of the cells in your pack is dumping. Rechargable batteries put out almost the same voltage untill the point they can't produce current anymore and they significantly lose voltage in a very short time period. Not like alkalines that slowly decrease.

And after like 10-15 minutes, check to see if you stuff is hot, like the motor, sppeed controll and batteries. If any of them are HOT, then stop running and let the stuff cool off.
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