MMM Combo 2200 a lot of cogging...
 

Today I received my MMM Combo 2200 and put it in my Losi 8ight-e (4s) (16th pinion)I have a lot of cogging instead of a smooth start ....

I am also using a MMM V3 and a NEU 1515/1/Y in my Emaxx on 5s and it is very smooth.
Are there different MMM V3s available ? The older one beeps 5s times on startup indicating that I am using a 5s lipo setup. The new one in the combo doesn´t...

If it doesn't beep 5 times, then the auto-lipo setting is probably not set correctly. It might be cogging because the LVC is kicking in. Take a look at it with the castle link and see.

Ok, I turned on auto-lipo ... this was my fault but the cogging still remains... It might be a problem with the very strong magnets inside the motor.

It should not be cogging, there is a problem somewhere. Make sure all you connection are good with good solder joints on the bullets.

There has been one other report of a bad solder joint - worth checking

I've seen bad solder joints from CC on more than one occasion... Fortunately they weren't on any of my CC items, but a buddy of mine has had a MM 5700 and MMM 2200 combo each with a single bad solder joint that produced extraneous cogging.

Realistically, that's not really a reason for cogging. It's more likely you have a bad connection somewhere.

Solder joints are fine ....

You have newest firmware in it? What lipos are you running, C rate?

I am using Kokam H5 30 C 5000mAh lipos .
Yes I have the newest firmware 1.2

Very hard to say then, Lipos sounds ok. Have you tried different setting for the controller? I would try reset all the setting to default and try then. But that just me, prolly wouldn't help anything.

Here's few thing that could cause cogging: bad solder joint, bad lipos, gearing, binding in drivetrain, (too long wires?), escs settings

If this is truly cogging, I would think it was a connection or soldering issue. Since you say they are ok, we'll assume they are. And gearing sounds ok, although 5s on a 2200 kv motor geared with a 16T pinion is gonna be fast.

Might seem to be a PITA, but you could take the MMM from your maxx and try it in the 8ight-e. If it still coggs, put the 8eight-e MMM back in and try the Neu 1515/1y from the maxx. Just trying to isolate the problem component.

Sometimes, a glitchy radio can seem like cogging. Try plugging a servo in the throttle port and see how it acts. Obviously, it should turn smoothly. Even if it does, ESCs tend to be more sensitive than servos. And/or try the radio setup from your maxx.

Try increasing start power on the MMM

+1 this is a tell tail way to find out. it could be a bad solder joint inside the motor? where the wires meet the windings. http://i183.photobucket.com/albums/x.../IMAGE_046.jpg

Holy out of focus picture batman. I think I can see something there but I'm not sure.

From far away, my g/f thought it was a bowl of ice cream with stuff on top! So yeah, maybe a better pic with the macro setting?

Maybe I expect too much ... here is a video of the "cogging" Castle 2200

http://de.youtube.com/watch?v=QR02Vf7Mw8Y (watch it in HD !)

You are just at very low throttle before the motor breaks the magnet/ pole attraction- so it looks to me. Once it is above that minimum rpm do you have any studdering issues?

Yes ... the studdering is only at a very very low throttle .... When the motor starts I have no issues ;)

That is not cogging! Have you tried it in your car? Motor/esc needs a minimum RPM to establish rotor position and function properly. cars/trucks/buggies all use gear reduction so that's not to much of an issue. I have aprox a 13:1 reduction on my REVO so every 13 turns of that motor only turns the wheel once. without a load on the motor you are going from nothing to about 20,000RPMs!

Ok, that video helps.

Increasing the start power setting in the MMM will help with that. Being sensorless, the ESC needs to see a certain amount of rpm to know where the rotor is. Increasing the start power will "tickle" the motor a little more to spin it up so it will get an rpm reading faster.

This thread will explain the MMM settings in more detail if you want.

You are gonna have a tiny bit of cogging at very low speeds no matter what you do. Usually, this isn't a big deal since most people don't run these systems at ~1mph, not to mention ESCs/motors are not nearly as efficient at partial throttle anyhow.

Ok, but the NEU 1515/1/Y runs a little smoother ;)

I have wondered myself too that little clitch, running at very slow speed. Really aren't a problem unless if you wan't to crawl with it :tongue:

sorry cell phone:na:

change your pinion to 13t and the cogging will be reduced
 

i believe if you change the pinion to 13t the cogging will be much less due to gear reduction and the thing will still fly.