Crunching noise from ecx tourment

T

Taite

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I have noticed since I have upgraded to brushless on my ecx tourment I have had a horrible crunching noice coming from somewhere when there’s even the slightest bit of pressure applied on the car.
Does anyone know what this is?
 
Pressure? Torque applied by the motor? Can you provide a bit more information? 2wd, 4wd, how long ago was the brushless upgrade done?
is this the first run after the upgrade?
The crunching sound you state, sounds like it could be a stripped gear, are the pinion gear and spur gear meshed properly?, any signs of wear on them? Could be a plastic gear internally to the gear box as well.
 
WithinU said:
Pressure? Torque applied by the motor? Can you provide a bit more information? 2wd, 4wd, how long ago was the brushless upgrade done?
is this the first run after the upgrade?
The crunching sound you state, sounds like it could be a stripped gear, are the pinion gear and spur gear meshed properly?, any signs of wear on them? Could be a plastic gear internally to the gear box as well.
Click to expand...
It is 4x4, by pressure I mean like going through long grass and up hills. The gears are fine checked these the upgrade was recent about 15 runs ago. I hope this helped
 
I didn't think about this before, it could also be the axle too, have you inspected the hex on the wheel side of the axle? is it slipping in the wheel? Is the set screw tight holding the axle onto the output shafts?
 
I have checked all of this and it still makes this noise without moving
 
Hi guys I'm a friend of Taite and also have a torment with the same problem. I have attached a video to show what is happening. Me and Taite have already tried to fix the issue by lock titeing the centre drive shaft grub screw(as shown in picture attached). However our fix did not work so it must be something else. This did not happen when I had the stock brushed motor so it must be something to do with the power of the brushless motor in it.

Here's the link to the video:
https://photos.app.goo.gl/xU9Cahw7J4FMi2ud8
 

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There was no sound on the video, for me amyways. Does it only do it at slow speed? Could be what's called cogging. Is this your first sensorless brushless system?
 
Yes this is my first sensorless brushless motor. It does it whenever you get to something that is difficult to get through like long grass (like in the video). It also does it when you accelerate really quickly.
 
TSElectronics said:
Yes this is my first sensorless brushless motor. It does it whenever you get to something that is difficult to get through like long grass (like in the video). It also does it when you accelerate really quickly.
Click to expand...

Sounds like cogging to me the motor you are using is underpowered and/or over geared. Too much load on the motor on initial acceleration but once it gets moving it's probably fine. I believe stock pinion is 12t dop down to a 9 or 10t pinion and see what happens.

I would not use a F540 (finned 540) motor and get a full 3650 size motor or even a 3660 motor. Depending on the kv or turn you get it maybe a little slower but won't cog as bad or any at all and run cooler.
 
Heyitsme said:
Sounds like cogging to me the motor you are using is underpowered and/or over geared. Too much load on the motor on initial acceleration but once it gets moving it's probably fine. I believe stock pinion is 12t dop down to a 9 or 10t pinion and see what happens.

I would not use a F540 (finned 540) motor and get a full 3650 size motor or even a 3660 motor. Depending on the kv or turn you get it maybe a little slower but won't cog as bad or any at all and run cooler.
Click to expand...

Thanks ever so much for your help. This sounds like the problem and I'll get a pinion gear with less teeth and when my motor goes I'll get a 550 or something like that to put in it. Thank you

Also thanks WithinU for that website it looks like an interesting read ?
 
Hey no problem. I am sure there are "better" more detailed explanations out there on the cogging subject.
It was just a quicky search and read for me, to better understand what Heyitsme was talking about.

I also ran across some information about how to help the cogging issue, but I didn't want to post it and not know if there were any validity to it.
But they discussed adjusting the timing on the motors to help with, or to eliminate the cogging. It had to do with adjusting timing on the motor.
 
TSElectronics said:
What do you guys think about these motors?

https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.co.uk/ulk/itm/253866488046

https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.co.uk/ulk/itm/143093053325

It's a waterproof 540 that doesn't have fins. I know it's from China but I don't mind waiting.
Click to expand...

The 4300kv motor should be fine on 2s lipos but 3s lipos you need to have bigger than a 60a esc. The 3660 3180kv will be slower than your current motor but will have more bottom end power (less cogging) so will need to be geared taller to achieve the same top end speed (or use 3s lipo). Same applies to the 3660 motor about running 3s lipos get a bigger than a 60a esc.
 
TSElectronics said:
So do you expect that the 4300kv would not have cogging problems anymore?
Click to expand...

I can't be 100% positive that it will get rid of all your cogging (stuttering) but that 4300kv is a stronger motor than that finned 540 motor.

Here's some comparison pictures of motor sizes and internal rotors.

F540 vs 3650
RmAvRgy.jpg


F540 rotor vs 3650 rotor
IBrI12m.jpg


What is in that finned 540 can basically
fH4T7SF.jpg


3650 vs 3660 motor
dw9aVbd.jpg


A 550 size brushless motor is roughly a 3656 can motor in between the 3650 and 3660 can motor.
 
Taite said:
It is 4x4, by pressure I mean like going through long grass and up hills. The gears are fine checked these the upgrade was recent about 15 runs ago. I hope this helped
Click to expand...
I'm not sure these cars are supposed to go through long grass...(at least the 2wd torment)
 
Another thing, if it is crunching or clicking, could be the transmission. If you have the metal transmission, then if it isn't lubricated correctly or you missed a bearing, then everything goes wrong with it. I should know-I went through 3 sets of gears before I finally got mine running correctly! And that was when I didn't have brushless! And it was all because I didn't have the gear mesh set, didn't adjust the slipper clutch correctly, didn't use the right lubrication, and missed putting in a very crucial bearing in the installation process.
 

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