Tekin ROC412 knocking noise
 

Hey Guys,

Just got a new setup, Tekin RS PRO with a roc 412 motor. Runs great but sometime when i stop, there is a knocking noise coming from from the motor. Any thoughts on what this might be? I did notice that the test leds on the ESC sightly flicker while the noise is occurring.

Video...

<iframe width="560" height="315" src="http://www.youtube.com/embed/I-OMJ8s57hQ?rel=0" frameborder="0" allowfullscreen></iframe>

Any ideas on what might be causing this?

Thanks,

Michael

Re: Tekin ROC412 knocking noise
 

Tiny bull frog or large cricket?

Honestly though I'm not sure. I have mine on the way and will say once I have it setup.

Re: Tekin ROC412 knocking noise
 

Sounds like your trim is off just a touch one way.

Re: Tekin ROC412 knocking noise
 

I just tried adjusting the throttle trim and it doesn't effect the noise. Still knocks... I'll trim it until the motor starts wants to move, trim it back and the noise starts up again. Did this for both forward and reverse, no change. Without moving the rig, restarting the ESC will stop the noise as well.

Anyone out there having this issue before?

If nothing, I'll open up a issue with Tekin..

Re: Tekin ROC412 knocking noise
 

I have no experience with this setup, but I have read a ton on this.

Since you are using the RS pro, check with this thread they have some great setup points and changed a few things. Maybe just one setting is off with your ESC.
http://www.rccrawler.com/forum/elect...roc-412-a.html

Wish i had a concrete answer for you but I don't. Good luck"thumbsup"

Re: Tekin ROC412 knocking noise
 

I know it's a dumb question, but have you recalibrated the ESC to the radio recently? If it's the trim or center that could do it.

Re: Tekin ROC412 knocking noise
 

Just call Tekin. They don't make any big deal out of helping out. No need to open an issue or anything. Try to get Ty or Jeremy...some of the other tech guys don't speak much crawlereze.

My only thoughts would be if your neutral settings are too narrow or if you're not calibrated to the center of neutral. But I run an MMP not an RS so am not that familiar. If you push the trigger slightly one way does the noise stop even though you're not yet moving? I would think that's how it would react if my previous guesses were correct.

Re: Tekin ROC412 knocking noise
 

Dbl post

Re: Tekin ROC412 knocking noise
 

I have that exact setup and it does not make any noises like that.

Re: Tekin ROC412 knocking noise
 

yeah,I have recalibrated the throttle a few times and still the same thing. I know it's not an issue with my throttle trim because as I adjust the trim the noise will stop if I reach the point where the motor is making the high pitch whine like it wants to move. Trim it back and the whine is gone and the knocking comes back in. Does this is both direction.

This doesn't happen all the time when the rig comes to a stop... Just random.

Without moving the rig, turning off the ESC and back on will make the noise stop. This probably rules out a bad sensor positioning on the motor.

I guess I'll have to escalate this to Tekin.

Re: Tekin ROC412 knocking noise
 

Is the TX/RX set to S-FHSS?

Or as WAM said try adjusting Neutral Width (dead band) to a higher setting. Stock is 4/5 so maybe try highest setting (13) and see what happens.

Re: Tekin ROC412 knocking noise
 

Nice vid for diagnostics. Being able to see the leds clearly and hear the sounds is excellent for figuring things out.

Looks like it is specific to being in nuetral and sounds active, as in passing power. Lets start with the basics steps to see if we can isolate it.

Active brake turned on in Hotwire?

Factory reset the unit to start from scratch. Press and hold Incr and Mode button for 5sec.

What software version? Reload the software if you have a Hotwire.

Pull sensor wire from motor.

Also be helpful if you can try a different BL motor, does not need to mounted.

Pull rx plug out of reciever. Unit should flash all leds telling you it sees no radio signal.

Put esc rx plug back in and remove the servo plug from rx.

Long shot but try a different radio and receiver if you can.

Could just be broke...

Re: Tekin ROC412 knocking noise
 

Okay, So...step by step

Active braking is turned off

I factory reset the ESC via the onboard buttons,
reload the 223 SW version, and put back all the settings. Increased my dead band form 5 to 50

Still Knocked...

While the motor was knocking, pull the sensor wire and motor stopped knocking.

Turned ESC off, Plugged sensor back in, restarted, drove back and forth a few times, knocking is back.

While knocking, pulled esc rx plug, continues to knock while all LEDs flashed, Plugged back in, still knocking. Pull servo plug, still knocking.

Don't have another BL motor to try out at this time.

All this was using a 4pl, tried it with a AE XP3-SS TX/RX with the same result.

So it looks to be related to the sensor circuit on either the motor or ESC...

I'll see if I can source another Bl motor but it's unlikely. Just to note that it doesn't seem to effect the over all performance of the motor while in motion. Just on random times after a slow crawl and stopping does this occur. Nothing is getting warm either.

Thanks for all the help so far guys!

Re: Tekin ROC412 knocking noise
 

Do you have to hit brakes abruptly to make it happen?

Can you coast to a stop and ever cause it?

Re: Tekin ROC412 knocking noise
 

Here is another vid showing how it starts. Basically it seems to start when it's slowing down form a crawl. not from high speed.

Here is a vid:

<iframe width="560" height="315" src="http://www.youtube.com/embed/J5xUca1Ap60" frameborder="0" allowfullscreen></iframe>


I turned off my drag brake and it seems to have stopped, but notice that randomly, just about when the motor comes to a complete stop, you hear it knock a bit. It's the same noise, but doesn't repeat like the previous video.

<iframe width="420" height="315" src="http://www.youtube.com/embed/YPHuYsBPX4I" frameborder="0" allowfullscreen></iframe>

But I do need my drag brake! :)

Thanks very much for all the efforts so far! Much appreciated.

Re: Tekin ROC412 knocking noise
 

Spun rod bearing..... =(

Re: Tekin ROC412 knocking noise
 

LOL, I figure going electric would have avoided that from ever happening!..dunno how else to get rid of it! Timing is already at 0.. ;)

Re: Tekin ROC412 knocking noise
 

How high is the drag brake set to? Reduce it to under 50% and see if it is still there.

Lets also try backing up to version 212 and see if it is still there.

Re: Tekin ROC412 knocking noise
 

Drag brake is set to 25 on the first vid. On the last vid I uploaded, drag brake was completely turned off.

I'll try with an earlier version.

Re: Tekin ROC412 knocking noise
 

When you unplugged the sensor wire, it quit making the noise, correct?

Correct me if I am wrong, but it sounds to me like a bad sensor...