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View Full Version : Nonlinear acceleration with 12000kV brushless motor


rojak
2015.05.14, 09:40 PM
Hi,
I own MA-020VE miniZ. Recently just upgrade the motor from ECO motor 5600KV to 12000KV motor.
With same ICS setup, with new motor, my car can't accelerate linear. I need to throttle a bit before the car move. Which is first mm of throttle, the car is no response. Please advise is it there is ics setting that I need to change?

LED
2015.05.15, 12:55 AM
You can try shifting your centre point and then adjust your end point. The problem then could be that it will be more difficult to get into reverse.

rojak
2015.05.15, 01:47 AM
You can try shifting your centre point and then adjust your end point. The problem then could be that it will be more difficult to get into reverse.
Tried that,but still same, after few mm of throttle, then my car move.

TheSteve
2015.05.15, 02:43 AM
The electronic speed control may be having a tough time starting a motor with such a high kV.

rojak
2015.05.15, 02:58 AM
The electronic speed control may be having a tough time starting a motor with such a high kV.
Is it anything that I can improve it?Like setting in ics?

Jshwaa
2015.05.15, 07:24 AM
With brushless control 'without sensor feedback', starting torque is something that needs to be dialed in, as the esc has no reference for how much movement results from the current it administers to the motor windings, so it is literally driving your motor blind.

Do you hear the switching of the ESC occurring within that first 'mm' or so of trigger pull?

If so, then the phenomenon you are experiencing is friction in the drive-train. Until everything gets smoothed out, it will take a minimum amount of throttle to break the friction trying to hold everything still. See if that phenomenon occurs with the motor itself, outside of the car. If not, then 'friction' is the gremlin here.

rojak
2015.05.15, 08:07 PM
With brushless control 'without sensor feedback', starting torque is something that needs to be dialed in, as the esc has no reference for how much movement results from the current it administers to the motor windings, so it is literally driving your motor blind.

Do you hear the switching of the ESC occurring within that first 'mm' or so of trigger pull?

If so, then the phenomenon you are experiencing is friction in the drive-train. Until everything gets smoothed out, it will take a minimum amount of throttle to break the friction trying to hold everything still. See if that phenomenon occurs with the motor itself, outside of the car. If not, then 'friction' is the gremlin here.

First mm not hear any switching sound.
Last night my tx gone haywire. My car cannot be control.After being reset,re-pairing with my car,then okay.
My car response is better after reset the remote.
One more thing, this 12000KV motor is sensitive with battery drop, I change with fresh charge battery, the acceleration is smooth,compare with used battery,my car is jerking during acceleration.

cowboysir
2015.05.15, 08:23 PM
I have experienced a similar jerky acceleration with a PN motor (not as high a KV). With certain cells i will get great racing for 12-15 min but on other cells I get a bad "cogging" effect while trying to accelerate.

This seems to happen when i use all available throttle fwd on my endpoints adjustment.

I have corrected this for the most part by taking 10% off my total th-fwd endpoint.

It has been suggested to me that my wiring from esc to motor might be flawed slightly on one of the three wires...i have yet to check but you may find success with this in your case.

As for finger travelling a bit before getting any actual motor movement you might try creating a higher throttle curve on your TX...by ramping up the initial takeoff point you may have some success getting a quicker start from the motor. I have set 2 different brushed motors like this to great effect.

rojak
2015.05.15, 08:26 PM
I have experienced a similar jerky acceleration with a PN motor (not as high a KV). With certain cells i will get great racing for 12-15 min but on other cells I get a bad "cogging" effect while trying to accelerate.

This seems to happen when i use all available throttle fwd on my endpoints adjustment.

I have corrected this for the most part by taking 10% off my total th-fwd endpoint.

It has been suggested to me that my wiring from esc to motor might be flawed slightly on one of the three wires...i have yet to check but you may find success with this in your case.

As for finger travelling a bit before getting any actual motor movement you might try creating a higher throttle curve on your TX...by ramping up the initial takeoff point you may have some success getting a quicker start from the motor. I have set 2 different brushed motors like this to great effect.
Hi,
What do you mean "creating a higher throttle curve"?Is it using ics?

cowboysir
2015.05.15, 08:57 PM
Im unsure if it can be done with ICS. I assumed you have a TX with programmable features....

If you do have a high function TX you might be able to find a section in your throttle area that can adjust the throttle ramp/map

rojak
2015.05.15, 08:58 PM
Im unsure if it can be done with ICS. I assumed you have a TX with programmable features....

If you do have a high function TX you might be able to find a section in your throttle area that can adjust the throttle ramp/map

I am using KT18,i notice there is 2 pin at the back label "sw" you think it can be done?

dameetz
2015.05.16, 11:47 AM
Try NARROW throttle neutral width - i cant remember what its call on the ICS programme but its the one with 3 options, Narrow - Normal - Wide. The default is set to Normal if I m not mistaken.

DMALMAD
2015.05.16, 05:55 PM
Im unsure if it can be done with ICS. I assumed you have a TX with programmable features....

If you do have a high function TX you might be able to find a section in your throttle area that can adjust the throttle ramp/map

In the ics you can change the throttle frequency to get a simmilar effect as throttle curve on the radio. The higher the throttle frequency the smoother the car will be but will have less initial punch. The lower the frequency it will be less smooth but will accelerate much quicker initialy. Also the higher the frequency the hotter the esc will get and the more strain will be put on the batteries.

rojak
2015.05.18, 08:54 PM
In the ics you can change the throttle frequency to get a simmilar effect as throttle curve on the radio. The higher the throttle frequency the smoother the car will be but will have less initial punch. The lower the frequency it will be less smooth but will accelerate much quicker initialy. Also the higher the frequency the hotter the esc will get and the more strain will be put on the batteries.
I see,but that setting is not available in ve ics.
Only got punch level and motor constant option.
By the way,issue has been solved.
After my tx gone haywire,i reset it back,re pair it with my car. No issue after that.