MMM v3 into therminal + hot motor???
 

Hey,

I was today bashing with my savage, till suddenly the car stopped. I heard the fan spinning and after a few seconds the car didn't moved at all, therminal shutdown...

The motor gets also very warm> 60+ degrees(140 +F). It even becomes more hot when you stop the car, when you drive it cools down....

Who knows what to do? gearing up will make the motor even hotter i think???
Or what else to do to get the ESC cool and the motor a bit cooler.

Greetz,
Joram

It would help if you gave us more info? Is this the motor in your xmod, or your full size electric car? Or maybe a cordless toaster?

for how long did you run..before this thing happen????and what kind of motor it is????

and the setting of your esc???

A smaller pinion gear will help lower ESC temps. But first make sure there isn't any binding in the transmission/differentials/bearings as binding could be the cause of excess heat.

loll
your faster than me:whistle::mdr:

@Lincpimp, read the text, i really said i ran with my SAVAGE,

I use a Savöx 4570 motor, 1800kv on 5S lipo.
Drove about 10-15 minutes when it suddenly happened.


The driveline is OK, runs normall....

Settings of the ESC are:

Brake setting: 3
Brake amount: 50%
Reverse amount: 70%
Punch control: disabled
No drag brake
Start power:HIGH

Greetz,
Joram

first thing reduce your start power to the lowest setting, this will lower your temps, and what is your gearing?

You can try lowering the start power to medium and punch control to something like 30%. These two alone should help a lot.

I was planning to adjust the start power to medium.

I'm also going tu se an UBEC, so that is also a lower temp. factor!

Gearing is btw, 18/47 (16/47 but I run Cen diff's)

Greetz,
Joram

The mmm already has a built in, but separate switching bec so using another one won't do anything.

It will lower the temps, it is tested!

It is in the print so it makes heat, if you won't use it won't heat the whole thing...

Greetz,
Joram

I'll try to explain again... Escs like the Mamba max and about every other esc that has a built in bec WILL get lower temps from an external bec. The mmm is different then all the other escs. It has a separate bec built into the bottom of the case. The bec shouldn't produce much heat at all...

We will see, before problems with the MMM where the Switching BEC....

Don't say my problems are cause of that, but i prefer an UBEC above the BEC from an speed controller!

Greetz,
Joram

Sounds like you got her all figured out then. :lol:

The MMM has a UBEC built into it as Metallover stated. If you go with an external UBEC your temps might drop by 1 deg. F, if that. Hardly worth it IMO. And the problems the MMM used to have with the BEC have been completely resolved, so the only reason I can imagine using an external BEC with the MMM is if you have a V1 or V2 MMM.

my V1 works fine:neutral:

I've been running my V2 using the internal UBEC with no problems at all.

Sounds like you need to lower the gearing some.

if after lowering the start setting with the ESC and its still too hot try lowering your gearing( smaller pinion, bigger spur)

Mine too :neutral:

lol my v3 works fine :)


adding an external BEC doesnt fix the problem, only hides it... it may have been proven to lower temps in esc's with a linear BEC. a switching BEC creates almost no heat.. But since you have it all under control i will stop talking..

I think it is crazy that he thermaled a MMM.:surprised:

haha, lol

It was not thermal shit.... Just a empty battery:intello:

But i assume it is normall then that the fan spins when the cut-off is working???

Did today some bashng with no problems, only fried AGAIN the stupid slipperpad:S

Greetz,
Joram

if your slipper is too loose, it will create more heat for both the motor and the esc. if you kept it a little tighter, it would help.

The flux slipper you have to pretty much tighten it up, even going 1/4 turn out and red loctite on the bastard it'll still come loose.

You don't wanna know how i have tighten the slipper up....

It is almost inpossible how tight it is, with blue loctite on it and that helps...

But the slipper just smokes... Spur becomes hot and i have a lot power so the pads burned away, i saw smoke from the car coming:intello:

I'm now using that bycicle repair stuff, what you can cut in you own way!
It is very sturdy and i make it fully covered.

Not only as a normal pad, but also in the middel around the shaft. Just make a round one and cut the hole for the shaft...

I hope you understand this what I say:lol:


I am also working on a mountingsystem with no slipperpads, so directly the spur to the shaft...

Greetz,
Joram

You'll want to keep the slipper no matter what. If you bypass it your magnet could come off the shaft in your motor on a bad landing. The slipper is there for a reason. A different pad material is probably your best solution.

Riley- why have a slipper? Buggies and truggies don't have slippers, and I'm sure many other people (as well as me) have had plenty of bad landings without their magnet detaching.

It can happen. It is also a little more important on a mt because there is more weight and larger tires being thrown around. I guess you could go without it, but you run a much higher risk of ruining your motor. It may not happen to everybody but you may just be the lucky one...

I think that there is an very low chance to ruin you motor with that...

Today my slipper was again the troublemaker... I'm going to screw the spurgear to the slipperhub with 3 screws, threw the spurgear. I drill the holes and use soe bolts with nuts.

I've everything on my truck bullterproof with the highest quality, but only that piece of ***slipperpad

Greetz,
Joram

sounds like its time to rebuild your slipper clutch

Why rebuilding.....?

Greetz,
Joram

to fix the problem.

and taking the slipper out of the equation is going to pass the blame to your diffs on the next failure. People dont usually run slippers on 8th scale cars because the drivelines are darn near bulletproof.

the savage has always been known to have weak diffs... so your choice... set the slipper up right with a rebuild or pay for new diff gears. 3 dollars or 40 dollars.

Don't think you have followed my BL project....

I run cen diff's, i have everything top of the bill!

I'm going tu screw the spur to the hub, there are no other alternatives...

Greetz,
Joram

Rebuild the slipper (replacement spring / washer / nut set is only $7) and replace the pad, tighten it up all the way then reinstall on the car, then hold the pinion and tighten it a tad more using a 7mm ring spanner as that tighten it some more

That has worked fine for me.

Don't think that is the problem...

The nut doesn't comes loose, only the pad just fries....

I'm going to screw it, an slipper is worthless with a high powerfull BL machine...

I've tried different designs spurs, savage style and savage x style slipper, nothing worked so that i can run twice with a pad...

Greetz,
Joram

IMO your problems with the spur is telling you there is a problem somewhere else, and the spur failing has been the equivilent to a fuse in an electrical circuit. A cheaper part failing to keep more expensive damage from happening, and any part can fail including a CEN diff

I have ordered an complete new savage Xss spurset:

http://www.jparts.eu/pages/popup.asp?foto=jp012.jpg

Greetz,
Joram

Slipper clutches weren't meant to be worthless. This result just means the Savage X slipper is worthless :lol:

Another more expensive alternative is a center diff. If you go this route you won't need a slipper clutch, but your drivetrain will be protected well still.

Don't think that will fit in the FLM chassis??

Greetz,
Joram

It will, just will require some custom pieces to make it fit. That's why I mentioned it would be a more expensive option :whistle:

Several have installed a center diff into their Savages, I am on of them:
http://www.rc-monster.com/forum/show...9&postcount=42
(those are old pictures)