Need in some coggin issue with a MMP

[Mister-T]

Hello,

I've some issue with a Mamba max pro that I intend to use on a custom short course truck on 4S lipo

About my setup:

- Mamba max pro used in sensorless only
- 4S lipo 5000 mah 20C
- Authentic Steve neu motors 1512/2D/F
- Gearing the shortest my motor mount allow (13 teeth gear)

Important : That motor have been succesfuly used in a 1/8 scale off road car with a mamba monster without issue.

My issue are with cogging when trying to go reverse , It can't start the motor and the motor cogg badly when running in reverse.
In such situation everything goes hot wire, ESC and motors.
When going forward the problem is different, the car is running OK and start up are OK 3/5 of the time but any fast change in speed (squezzing the throttle by short pulse) result into a brutal cogging/ full braking effect, almost a lock down , It's bad for the mecanic and extremly disturbing to drive

I thought it was a bad connector issue, so I redo all motor/ESC soldering job - still the same problem

I tried several software and setup, with that MMP the best (or least bad cogging situation) was with the 1.26 or the 1.32 without punch control and torque limit set to 7 (i did the kv test), but the problem remain both on backward and forward.
For backward issue, I did test by simply switching phase so a forward action would make the car go backward (checking if it's a mechnical issue). The motor then run smoothly in reverse motion but cogg If I apply a burst of acceleration( the typical forward problem)
I tried with a different battery without noticiable improvement.

In the end I just unplugged the MMP pro an tried to mount my mamba monster to run the motor (just to check the motor). I could drive the motor in forward motion flawleslly and backward does work too...

I'm seriously running out of idea, I wanted to use MMP I wonder if it's some kind of hardware damage or software issue ?

[scarletboa]

What's your timing set at?

[Mister-T]

I have tried both 0, 5 and 10°.
10° gave the best result (less failure at launch)

[Mister-T]

I just looked @ rctech, it seem there is quite a few people who run into such strange behaviour and often worse

I did a small movie last night,

http://www.youtube.com/watch?v=cEByKPPRhRM

from 00 to 0.10
You can see forward working ok (it doesn't no work so well when the car is on the ground because it often cog badly right in the middle of an acceleration)

From 0.10 to 0.31
I'm trying to go backward with different level of speed and show some bad cogging no matter what.

From 0.31 to the end
Going forward and doing intermediate speed you can hear that at certain RPM it's isn't smooth at is sound a little rough a like a phase was out of synch around (0.47)

I did the same test with the monster max, and didn't run into such problem with it

Try going back to an older version of firmware. The newer releases have lots of bugs.

[suicideneil]

Ditto, firmware is the first thing to look at assuming it isnt a poor joint or connection / radio issue.

Anything newer than v1.24 can cause poor throttle control from a standstill & at low rpms- I would see what version the esc has now ( under the software tab ) and then try the latest, or work backwards until you get smooth control again.

Timing shouldnt be an issue really, set it on the lowest or low timing and it'll run fine with good temps- start power on low too.

[Mister-T]

Read the first post ;)

I've already tried 3 different firmware 1.24 1.26 and 1.32, the 1.26 was the best, but the backward bug remain the same and coggin on acceleration is still present as well
I redid the soldering job on connectors and I use the very same connector on my monster max on the same motor wihtout issue (extra long 4 mm connectors)

[suicideneil]

My bad, didnt spot that.

Im not really sure what to say- sounds almost like the esc is 'miss firing' rather than the firmwre being the issue then; could be a few or several bad fets, especially if the esc is getting really hot quickly like that ( and the motor works fine with an MMM, right? ).

I would say it's time to send the esc in and get it looked at / repaired or replaced- form on the support page of the castle website.

[Mister-T]

do you know if it's take a lot of time for CC to answer email ? i've send an email the 22 @the support adress and i only got an automated answer

[suicideneil]

Email responses can take a while yeah, it might be worth PMing a rep here.