My Bomber is smoking motors

[k0Re7]

I have a bomber with all stock gearing and lots of upgrades, but i was out trailing the first time and my 35 turn axial motor started smoking so i stopped. I had to get a new motor from the LHS, but all they had was 27 turn.

So i put that in and made sure the mess was fine. well that one started to smoke too, but said the hell with it and keep driving the trail. It finally stopped working. Motor got so hot that the plastic fan melted and stopped the motor from turning.

Well i had a spare 27 turn from the LHS and there was a small easter trail crawl, so i put another new motor in and same thing happened. i know it was likely going to happen. It only took about 20 mins, the motor melted the fans inside the motor and 3S 5200 LiPo was at 3.8 volts per cell.

I was going to get a 55 turn, but decided to wait and try and figure out what is going on. I figured why waste another $15 on motor to have it get so hot it melts the fans again. I am just getting into RC, so i am still learning.

So my Axial AE-5 junk? Is the gearing wrong for 27 turn and 55 turn would be fine? Could it be one of my batteries? I have emailed Axial, but nothing back yet (2 days now).

k0Re7

 

[Wraithnoob]

What type of batteries are you using? Depending on drive style and how heavy your rig is will strain a motor. I would say a 35t should be fine for most normal driving. If you want to stay with a brushed motor i would buy a much higher quality brushed motor from Holmes hobbies or tekin and you'll be much happier than always replacing cheap motors.

 

[rngrchad]

How are you setting your gear mesh? Look for drag on the driveline somewhere or binding. Do your tires turn easily by hand? Something else is going on here other than "cheap brushed motor" problem. Start pulling drive lines and inspecting each part and piece in your gear train. What batts?

 

[k0Re7]

(2) Rage 3S 5200MAH 11.1V 3S 30C LIPO SOFT CASE BATTERY
One Onyx 2S 5000MAH

When the motor is not connected it seems fine.

 

[rngrchad]

Sounds like you may have an ESC issue.....ill let the pros chime in. When you say "a lot of upgrades" did you upgrade your electrical?

 

[Alexander_0_1]

I'd like to know how much heavier you've made it. Or can you run out a list of the stuff on your bomber?

 

[snapon boy]

You have a binding problem. You should also drop you spur gear down to a 10t for a while and see if it helps. Get a temp gun and start checking motor Temps every 5 mins,also check transmission and esc Temps. To kill 3 motors something is not ship shape

 

[k0Re7]

Upgrades are:

Beef tubes (both front and back)
VP stage one wraith kits
VP VVD's
VP Steering links
SSD Scale Steel Driveshaft Axial Yeti
SSD 2.2" Rock Racer Beadlock Wheels (Black)
MUD SLINGER 2 XL 2.2"
All aluminum links

That is what I can remember off the top of my head.

 

[Alexander_0_1]

That doesn't sound that heavy at all...I'd check for binding in the power train first, or too. When is it cooking motors when you use your 3s, or your 2s lipo?

A 5200mAh 3s lipo must be pretty heavy, I use a 3s 3700mAh soft case.

 

[rngrchad]

Stock gearing is 64/12. Is that what your running? It's stamped on the gears.

 

[k0Re7]

Yes stock 64/12 gearing.

 

[ostewart]

I smoked a 27t on stock gearing, change the pinion to 10t for a 27t motor.
I think those tyres are taller than stock too so that will act as if you geared up a little due to the extra height of the tyre.

 

[k0Re7]

the tires are a little bigger then stock. I decided to put the wheels on last night to check for binding. It rolls free. So i am going to stop at LHS and pick up a 55 turn tonight and see what happens. I just want to drive my rig this weekend. 4 days and nothing on my email to axial.

 

[Rjohn929]

Are you binding up while running? The 2 minutes I tried mine with the stock electronics I noticed the motor really has very little power even on 3s and binds up over the smallest of obstacles. Smelled like it was burning over the first set of rocks I went over. As long as everything is rolling freely (try pulling the pinion and check the drivetrain for binding) I would ry a traxxas 550 instead. Still cheap but better then the Axial stuff, unless you want to go brushless.

 

[k0Re7]

I will go brushless at some point, but for now i want to stay brushed. I may try a 550. Thanks.

 

[HahnsB2]

The Bomber tranny is higher geared than a SCX-10/Wraith tranny, really need to drop down to a 10t pinion with a brushed motor.

 

[k0Re7]

So if i go with 35 turn or higher i should be fine then? I think i am going to get a 55 turn tonight.

 

[JohnRobHolmes]

The Bomber tranny is higher geared than a SCX-10/Wraith tranny, really need to drop down to a 10t pinion with a brushed motor.

This!

 

[84yoda]

So if i go with 35 turn or higher i should be fine then? I think i am going to get a 55 turn tonight.

Get the 550 can 21t titan. Stock gearing. 3s."thumbsup"

 

[k0Re7]

Well this what Axial had to say:

Thank you for your recent email.

That high voltage, 3s, can work with 540 motors but the life of the brushes is
normally pretty short. In my experience, these types of brushed motors last
much longer and you have less problems with 2s voltage levels. I think the
failure of the motors is strictly related to use on 3s power.

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Well that does not help much at all.