Mamba Max Cogging Issue?

[rc10mike]

I just got my new 5700 system installed im my pede. Im using a Jr Xs3 with a good 3300 matched pack. The antennas are in good shape. Whenever I drive at a low speed I get cogging until about 1/2 throttle. Also, when going from reverse to forward. Im not mashing the throttle eiyher. Sometimes if I move the throttle really slow, I can get it to accellerate w/o cogging.

My question is: How much cogging has anyone else experienced with these systems?

[bdebde]

turn the "start power" setting to high

[rc10mike]

Thanks Ill try that. I just wanted to be sure mine wasnt defective...

[rca]

cogging can happen when overgeared, I do get the coggin when reverse to forward too but its no major issue to me, shawn has mentioned that this will be taken care off once they finish their first priority on the software update :)

[rc10mike]

Well I tried the start power on high and it didnt help. I know its not overgeared 14/86 Pede Masher 2k. When will this software update happen?

[tcolesen]

Maybe you have a bad system? I get almost no cogging with the Mamba Max ESC and a Feigao 8L on 4s Lipo in a heavy 1/8 buggy.

[SpEEdyBL]

You might have loose battery or motor connections.

[Rufus]

I'm experiencing similar cogging on my xxxt. Tried several settings without any success. I've placed a question under the Mambamax factory answers thread, so Castle should answer soon. I get the cogging even with the factory defaults... good luck fixing that cogging!

[RPC Werx]

Batteries, Batteries, Batteries.......
These systems draw alot of current. I suspect it may be insufficient power. If you can, try putting two batteries in parallel, if it doesn't solve the problem then you have other issues. But from what you have described, it sound like a power thing. Good luck

[TheSteve]

I would say guys have a poor connection somewhere in your power system, a defective battery or there is always the chance the Max is defective.
With a good pack and solid connections you should see no cogging at all.(unless you massively overgear it - even then you shouldn't see much)

[chilledoutuk]

i agree with rpc_werx it does sound like the batterys cant supply the jungle juice these babys need.
If his test does show that your problem lies in your batterys then perhaps you should invest in some nice GP cells.
Also adding a larger capacitor will also help if the problem is your cells not giving enough juice.

I have no experience with the elite cells but they look to be about the performance of gp3700 but its hard to tell on cheapbatterypacks.com website as they only plot a graph for 30amps.

[glassdoctor]

Mine have never cogged at all in my 1/10 cars.

I get occasional stutter in a 10lb 1/8 scale, but even there it never cogs at all once the car is moving. It's only from a dead stop, and only sometimes...

If it is cogging as you are accelerating it's not right. Follow the advice on the batteries first, and make sure the radio is not at fault.

[rc10mike]

Connectors are good. So thats not it. I swapped receivers. So thats not it. I messed with the start power settings. So thats not it either.

Whats weird is when I completely mash the throttle, I dont experience cogging. It only seems to do it 90% of the time when I go slowly from reverse to forward, and about 60% of the time with slower starts (not mashing).

[rc10mike]

The first time I set up the esc I held the motor in my hand and reved it up a few times, you know, just to hear it. I noticed that it started to get warm pretty quickly!


Also I noticed that by simply doing some running in the parking lot, the motor and esc were pretty warm. Id say 120-130 after about 5min. I thought these systems were supposed to be efficient! With the gearing Im using, I didnt even expect it to get warm. Im afraid that it will thermal by the end of the pack! The drivetrain is super smooth, and gear mesh is perfect.

5700, Stampede, 14/86, Masher 2ks

[glassdoctor]

It's possible to have a system run cooler... but 120-130 after 5 min is very good imo. What was the outside temp?

When running brushed motors that would qualify as "ice cold".

When my stuff is that cool I'm very very very happy

[TheSteve]

The first time I set up the esc I held the motor in my hand and reved it up a few times, you know, just to hear it. I noticed that it started to get warm pretty quickly!


Reving up a brushless motor in your hand will always make it hot very very fast. Without any load they run very inefficiently - its also the easiest way to break the rotor - but thats not something you have to worry about too much with a 5700 and 6 cells.

Do you have any pictures of the setup?

[rc10mike]

Ok, so maybe I over reacted a little! Better safe than sorry!

Anyway back to the cogging. Outside temp was about 76. I know some people in here have pedes. No pics yet. You think 14/86 is too high? I was under the impression that you could gear brushless higher than brushed (bigger pinion). I used to run LRP/3 Star in my pede with the same gearing and had none of these issues.


(Still waiting on 3s 6000 lipos from Maxamps. Order placed on 19th and they still havent shipped.....)

[JohnBee]

Running a 5700 under 3S will be insanely fast. - Can't wait to try it myself on our FLM Stampede :p

[rc10mike]

Just a question for all those that have ordered from Maxamps. How long did it take to receive your order?

Oh, Im still having cogging problems too...

[tcolesen]

If you haven't received your order, give Maxamps a call. I placed a custom order that Austin said would ship within 2 days, and it didn't end up shipping until a week and 2 days later, which happened to be the day after I called them.

[Shawn Palmer]

RC10Mike:
Give our tech support dpt. a call on Monday please. We'll need to hear "blow by blow" what's happening in detail, and we can get it figured out. Basically the way the Max's work, if you're seeing something you don't like - it's either radio interference or a bad ESC/Motor.

For radio clean-up:
Make sure to have the Rx and especially the antenna as far away from the ESC and motor as you can. High power systems can be radio unfriendly occasionally. Braiding/tightly twisting the ESC to motor wires can help, as well as keeping them as short as possible. Give these a shot over the weekend, and maybe re-arrange some things in the Pede if possible, and let us know what happens please.

Shawn

[rc10mike]

Thanks Shawn, I was pretty much waiting for you to respond!

As for the receiver, its on the front and the esc is in the back, about 6in apart. Im using Jr xs3 radio and Ive tried 2 different rs300 receivers, both with same effects.

[Shawn Palmer]

Thart's very odd. If the ESC and/or motor were geting hot, I'd automatically say something was wrong there and start working on getting you a new system to compare/contrast. The temps are way cool though.

Are those rs300's xtal Rx's or synth?

I run an XS3pro as a personal radio (after driving everything at work) and really love it.

Have you tried dropping the timing advance to lowest and see if there is any difference?

Shawn

[JohnBee]

I hate to break into this thread but I just wanted to put in my two cents also.
I just received a MMax today and decided to try the ESC on my setup. Originally I run a Genesis Pro A100 /540-8S, I swapped the A100 with the MMax and it coggs at low speeds also. I wouldn't say until 1/2 throttle though. More like 1/4. I swapped again with my A100 and it runs clean on the same pack.

I tried with both 6 and 7 cell 3600 packs. Same outcome.
I can't say for sure why but it does feel like interference glitching more than cogging. I will try a few more changes to see if I can't change the outcomes. I will say, that I am a little disapointed though.

[Shawn Palmer]

Hi JohnBee:
Like rc10mike has going on - something's not right. Shoot us a call on Monday and we'll help you get it figured out one way or another.

Shawn

[JohnBee]

Thanks Shawn, I will call on Monday first thing.

[JohnBee]

SUCCESS!

I don't know which of these are to blame but after putting in a fresh pack of batteries in our remote, twisting the wires to the motor and redoing all the connections on the ESC it's smooth as silk from 0 to 100%

In fact... it can really crawl smoothly on 6 cells compared to our Genesis Pro!
Very impressive indeed.

[rc10mike]

Ok, I made a harness to put 2 batts in parallell. This helped a little bit...I can accellerate faster w/o cogging. It still cogs when im going from Rev to Fwd, no matter how slow I do it! I can go from crawling rev to crawling fwd and jer,jer,jerk!

I also tried lower gearing and timing advance to lowest and it made no difference.

[RPC Werx]

Ok, I made a harness to put 2 batts in parallell. This helped a little bit...I can accellerate faster w/o cogging. It still cogs when im going from Rev to Fwd, no matter how slow I do it! I can go from crawling rev to crawling fwd and jer,jer,jerk!

I also tried lower gearing and timing advance to lowest and it made no difference. :D

I think cogging from Rev to Fwd is the nature of a sensorless system. As long as it doesn't cog during acceleration, you're good to go.

GP3300's 6 cell @ 20C discharge =66 amps x 2(parallel)=132 amps x 6 volts=792 watts of power. More amps than this set up needs.
6 volts x 5700=34,200 rpm. Geared 14/86=at least 30mph.

GP 3300's 12 cell @ 20C discharge = 132 amps x 12 volts=792 watts of power. Less amps = less heat = more efficient.
12 volts x 5700=68,400 rpm. Geared 13/90= 50+MPH, and better acceleration.

Good luck, and enjoy BL MM power

[ElectricThunder]

:D

I think cogging from Rev to Fwd is the nature of a sensorless system. As long as it doesn't cog during acceleration, you're good to go.

GP3300's 6 cell @ 20C discharge =66 amps x 2(parallel)=132 amps x 6 volts=792 watts of power. More amps than this set up needs.
6 volts x 5700=34,200 rpm. Geared 14/86=at least 30mph.

GP 3300's 12 cell @ 20C discharge = 66 amps x 12 volts=792 watts of power. Less amps = less heat = more efficient.
12 volts x 5700=68,400 rpm. Geared 13/90= 50+MPH, and better acceleration.

Good luck, and enjoy BL MM power :)..

[chilledoutuk]

GP 3300's 12 cell @ 20C discharge = 132 amps x 12 volts=792 watts of power. Less amps = less heat = more efficient.
12 volts x 5700=68,400 rpm. Geared 13/90= 50+MPH, and better acceleration.

Just to point out a typo that should be 66 amps when there in series so 66amps x 12volts =792watts