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Old 09-05-2011, 06:05 PM   #1
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Default SXX Competition Version 2 Brushless (brake problem)

Hopefully someone can give some ideas. Basically it's a brand new ESC installed in my new Team Associate 1/12 pan car.

I am new to electric cars - just an FYI.

Anyway, basically I don't seem to have a brake at least not after the motor stops spinning.. When using my Airtronics MX-3X radio, the motor will slow down or stop when applying the brake, however the car still rolls. There seems to be almost no resistance on the motor once it stops turning therefore the car continues to roll.

Another test I have done is to apply full brakes while the car is at rest then pushing the car forward. It rolls without much resistance. I have tried playing with the radio settings but that didn't help either.


There doesn't to be anything on that ESC that can be adjusted in ref. to the brake.

Anyone have any ideas or information that may help me.. Like I said I am new to electric cars, but I would think that the brake would work a little bit better than this.

thanks,
Tom
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Old 09-05-2011, 06:19 PM   #2
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Originally Posted by tomekz View Post
Hopefully someone can give some ideas. Basically it's a brand new ESC installed in my new Team Associate 1/12 pan car.

I am new to electric cars - just an FYI.

Anyway, basically I don't seem to have a brake at least not after the motor stops spinning.. When using my Airtronics MX-3X radio, the motor will slow down or stop when applying the brake, however the car still rolls. There seems to be almost no resistance on the motor once it stops turning therefore the car continues to roll.

Another test I have done is to apply full brakes while the car is at rest then pushing the car forward. It rolls without much resistance. I have tried playing with the radio settings but that didn't help either.


There doesn't to be anything on that ESC that can be adjusted in ref. to the brake.

Anyone have any ideas or information that may help me.. Like I said I am new to electric cars, but I would think that the brake would work a little bit better than this.

thanks,
Tom
I'm thinking you did not calibrate correctly, it is easy to mis-calibrate w/LRP the first time. The big thing is realizing that you will leave in neutral, then hit 'set'....hold full throttle then hit 'set'...hold brake, then hit 'set'. When you release the brake it will be ready to use. Give that a shot.
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Old 09-05-2011, 06:41 PM   #3
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I'm thinking you did not calibrate correctly, it is easy to mis-calibrate w/LRP the first time. The big thing is realizing that you will leave in neutral, then hit 'set'....hold full throttle then hit 'set'...hold brake, then hit 'set'. When you release the brake it will be ready to use. Give that a shot.

I have done that exact thing a couple of times. I don't think that is the problem. The ESC has LED's that show when full brake is applied therefore, I don't think that is it.

My guess is that the ESC isn't applying enough current across the motor and it still moves without much resistance.
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Old 09-05-2011, 06:43 PM   #4
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If your running a 17.5 and some of the big pinions, it could be the gearing that makes the brakes feel soft too.
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Old 09-05-2011, 07:07 PM   #5
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If your running a 17.5 and some of the big pinions, it could be the gearing that makes the brakes feel soft too.
That might be it.

I am running 17.5. With a 71T spur and a pinion of 52T. You think that could be the problem.
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Old 09-05-2011, 07:51 PM   #6
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What is your Throttle High End Point Adjustment set to on your radio? Check this: EPA TH H setting range is 0%to 140%. The default setting is 100%. Set your value to 140 then recalibrate and see if this gives you more brakes
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Old 09-05-2011, 08:07 PM   #7
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What is your Throttle High End Point Adjustment set to on your radio? Check this: EPA TH H setting range is 0%to 140%. The default setting is 100%. Set your value to 140 then recalibrate and see if this gives you more brakes
idbdoug
Just tried your suggestion. No change on brake, but throttle was acting up on any setting above 135 on full throttle.
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Old 09-05-2011, 08:17 PM   #8
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Just tried your suggestion. No change on brake, but throttle was acting up on any setting above 135 on full throttle.
Ok set your brake to around 120 and recalibrate to this setting. After calibration run up value to max(but don't recalibrate after setting max value) and see if this corrects the problem. I misread earlier and thought throttle was the problem not braking
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Old 09-06-2011, 10:39 AM   #9
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That might be it.

I am running 17.5. With a 71T spur and a pinion of 52T. You think that could be the problem.
It could be a setup problem, so try what the other guy is suggesting, BUT, when your running the big pinions they act as a big flywheel and once the get spinning you require more brakes to slow them down. Unfortunately thats just one of the by products of big pinion racing.
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Old 09-07-2011, 06:55 AM   #10
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Ok set your brake to around 120 and recalibrate to this setting. After calibration run up value to max(but don't recalibrate after setting max value) and see if this corrects the problem. I misread earlier and thought throttle was the problem not braking
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No,
still no luck......
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Old 09-07-2011, 09:01 AM   #11
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What is your Throttle High End Point Adjustment set to on your radio? Check this: EPA TH H setting range is 0%to 140%. The default setting is 100%. Set your value to 140 then recalibrate and see if this gives you more brakes
idbdoug
Try setting it to 100%, then calibrate. Then increase up to 110-115%
And/or reverse the 'servo' direction for the throttle, then repeat the above.
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Old 09-07-2011, 02:05 PM   #12
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Try setting it to 100%, then calibrate. Then increase up to 110-115%
And/or reverse the 'servo' direction for the throttle, then repeat the above.

I have tried the 100%, then calibrate.. No change in the brake.

Why would I want to do the reverse 'servo' option?

T
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Old 09-07-2011, 04:25 PM   #13
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Quote:
Originally Posted by tomekz View Post
Hopefully someone can give some ideas. Basically it's a brand new ESC installed in my new Team Associate 1/12 pan car.

I am new to electric cars - just an FYI.

Anyway, basically I don't seem to have a brake at least not after the motor stops spinning.. When using my Airtronics MX-3X radio, the motor will slow down or stop when applying the brake, however the car still rolls. There seems to be almost no resistance on the motor once it stops turning therefore the car continues to roll.

Another test I have done is to apply full brakes while the car is at rest then pushing the car forward. It rolls without much resistance. I have tried playing with the radio settings but that didn't help either.


There doesn't to be anything on that ESC that can be adjusted in ref. to the brake.

Anyone have any ideas or information that may help me.. Like I said I am new to electric cars, but I would think that the brake would work a little bit better than this.

thanks,
Tom
So you are saying once the motor stops, the brakes don't work ?
This is of course 100% normal.

Do the brakes have an effect while the car is at racing speeds ?
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Old 09-07-2011, 06:12 PM   #14
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So you are saying once the motor stops, the brakes don't work ?
This is of course 100% normal.

Do the brakes have an effect while the car is at racing speeds ?

That is what I have been trying to figure out, what is normal. I am new to electric cars. I would have assumed that the once the motor stops spinning I would have a little more brakes than what I got though.

I guess I could live with it, however, one example where I am having issues.
Let's say I am going driving on a fast long straight and start braking at the end, the brakes work well enough to slow the car down, they stop the motor from spinning, however, than the car still moves because there is no resistance anymore from the motor and the car continues to move still too fast for the corner.
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Old 09-07-2011, 07:24 PM   #15
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Originally Posted by tomekz View Post
That is what I have been trying to figure out, what is normal. I am new to electric cars. I would have assumed that the once the motor stops spinning I would have a little more brakes than what I got though.

I guess I could live with it, however, one example where I am having issues.
Let's say I am going driving on a fast long straight and start braking at the end, the brakes work well enough to slow the car down, they stop the motor from spinning, however, than the car still moves because there is no resistance anymore from the motor and the car continues to move still too fast for the corner.
There is no mechanical brake action with electric motors.
The esc can only drag the motor down to a low rpm, and that's all there is.

12th scale electric is all about corner speed, there is very little need, if any for brakes, especially at stock class speeds.

Since you're new to 12th scale, HERE is a link to tons of info on building and tuning your new car.

btw. Welcome to 12th scale, this is one of the most fun and inexpensive RC classes around
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