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Miko
2007.05.14, 04:18 AM
After installing better fets my car goes forward at the same speed as before (I have atomic awd stock motor which should gain more power with turbo). Only backward my car goes like ....... fast :cool:. I also check my fets as on the topic at this forum and there was nothing wrong. What is the problem?

Aurora
2007.05.14, 10:42 PM
Miko,

If you switch the motor wires around and check the EPA for both forward/back, will it make any difference? If the same issue presist, then it is more likely it is an isolated issue with the board/fet but not the motor/remote.

I read from other experienced member here that it is possible to damage the fet with heat/static, and it might not damage it to the point of not working, but definitely the performance will suffer. Do you think that would be the case for your installation?


For myself, I did stack fets on my AD board twice, and usually I have a bottle of compressed air handy, and if I feel there is intense heat during soldering, I would just use compress air to blow it cool.

Another thing I always do is just before and after the fet install, I always use a multimeter to check for connectivity, make absolutely sure the right pads/pins are connected and no wrong connection.


Hope this helps. :)

Miko
2007.05.15, 12:09 PM
Well I tested the motor with my brothers car which has stock fets and there was same problem. I cant understand why this is happening. Is is possible that theres something about the motor?

Ninja
2007.05.15, 08:01 PM
sounds like the brush on the + side is worn out
Simply replace brushes

eztuner12
2007.05.15, 11:29 PM
Miko,

If you switch the motor wires around and check the EPA for both forward/back, will it make any difference? If the same issue presist, then it is more likely it is an isolated issue with the board/fet but not the motor/remote.

I read from other experienced member here that it is possible to damage the fet with heat/static, and it might not damage it to the point of not working, but definitely the performance will suffer. Do you think that would be the case for your installation?


For myself, I did stack fets on my AD board twice, and usually I have a bottle of compressed air handy, and if I feel there is intense heat during soldering, I would just use compress air to blow it cool.

Another thing I always do is just before and after the fet install, I always use a multimeter to check for connectivity, make absolutely sure the right pads/pins are connected and no wrong connection.


Hope this helps. :)

Mybe out of topic but, did you stacked AD Board?
How it performs? do you had any problem/
I asked to Kyosho Japan about stacking the AD band FM, and their response was " Please DO NOT STACK FETs to the AD Band"
Thx

Miko
2007.05.16, 01:51 AM
..........

Aurora
2007.05.17, 04:46 AM
Miko,

One way to be absolutely sure is to find another stock motor to test on your car and also on your brother's car, if nothing goes wrong with either, then it is 100% sure it is your motor that is out of order.

I think Ninja is very likely to be right about the brushes, did you check them to see whether they are worn out?



Mybe out of topic but, did you stacked AD Board?
How it performs? do you had any problem/
I asked to Kyosho Japan about stacking the AD band FM, and their response was " Please DO NOT STACK FETs to the AD Band"
Thx


Eztuner12,

Sure I did...heck my car only live once! LOL :D

At first I was trying to install a Spider board on the AD band...but without making sure 100% which line solders to what...I ended up installing it on the AM board, but unluckily it still went wrong with all the precaution I have taken.(As a matter of fact, still didn't get around to email them again and still didn't hear any reply from them either)


Anyway, back to the topic. I ended up stacking two of my AD band board with a 2x3 config (4562), and man, both of them did spectacular and definitely love it. Now they are running with Xeric and T2 just fine.

I think the extra precaution of preventing overheating and static did me good. As for the 2x3, one will need 3 fets on top and 3 fets at the bottom(1 stacked on each side).

One good trick is to stack the fets with solder before soldering the 'stack' to the board...that way you will reduce risk of overheating the board.

And most important of all make 200% sure the direction of all the fets are going the right way(take picture of the 3010 fets before dis-soldering them for reference), orelse all ends in ruin.

Good luck, and I am sure you will love the result.
:)

Miko
2007.05.29, 11:36 AM
Miko,

One way to be absolutely sure is to find another stock motor to test on your car and also on your brother's car, if nothing goes wrong with either, then it is 100% sure it is your motor that is out of order.

I think Ninja is very likely to be right about the brushes, did you check them to see whether they are worn out.


I checked with the awd stock one and both cars worked well. So I opened the atomic motor and I found the other brush was a little smaller than the other. So I ordered new brushes and I fit them to my motor. But the problem still was, not helped at all. :( :eek:

Miko
2007.06.01, 01:37 AM
Still feels the motor is the problem. I did set it to AAA battery and it rolled more when I connect plus wire to negative and negative wire to positive. Should I just buy a new one or is there something to do?

Aurora
2007.06.05, 12:39 AM
Miko,

It sounded like it is not a board/fet problem, since you mention your car and your brother's car work the same with a stock motor.

And if you have changed the brushes, and the problem presist, it is also not likely to be a 'brush' problem.

Finally, the only thing I could think of is either an armature off-balance or magnets alignment problem. I am not experienced in motor science--but maybe the artmature is really off balance or the magnets are misaligned inside the case?

Anyway, if those are not the issues, then I'd recommend getting a new motor; if the budget allows, the current choices are abundant.