Holmes Motor overheated

[Gomiband]

I was in the front doing some slow crawling with my wraith just now. I was running for about 10 minutes when I noticed a burning smell then lots of smoke.

I hurried up and tore everything apart and threw a temp gun on the motor and it was 185 degrees.

I have weighted front tires, I'm running a Holmes crawl master pro 540 16t with the torque master brxl.

Any advice as to why things went thermal on me? What gearing should I be running etc?

[allanon1965]

Your gearing should be at least 5.25.. What gearing are you at right now?

[Gomiband]

It's a 20t pinion and I honestly don't know what the spur gear is off hand, I think it's an 80t. Doesn't say on it.



To be safe if I'm running 20t pinion what should the spur gear be? Or I guess the question is what should I be running period?

[Eric0424]

Looks like an 80 tooth spur. Bump up to 87t and/or a 15-16t pinion. If your motor smells, chances are it's toast depending on how hot it actually got. It may still have some life left, but I would at least recommend replacing the brushes. Heat pulls the oils/lubricants out of motor brushes and can/will weaken the magnets.

[allanon1965]

I think Holmes says a 16t is needed so the motor won't overheat...

[Gomiband]

Originally Posted by Eric0424

Looks like an 80 tooth spur. Bump up to 87t and/or a 15-16t pinion. If your motor smells, chances are it's toast depending on how hot it actually got. It may still have some life left, but I would at least recommend replacing the brushes. Heat pulls the oils/lubricants out of motor brushes and can/will weaken the magnets.

Oh she's a smelly for sure. Still emitting burnt stank.

[Norton]

How many cells were you running?
This is from Holmes page: IMPORTANT!! For use in the Axial Wrath on 3s lipo (11.1v) you must use a 16t pinion to avoid overheating the motor!!

[Eric0424]

Originally Posted by Gomiband

Oh she's a smelly for sure. Still emitting burnt stank.

It's probably beyond salvage, I've had a few of those myself.

If/when they get hot enough they can also melt the insulation on the windings.

Also noticed this on Holmes web site regarding the Crawl Master 540's.

IMPORTANT!! For use in the Axial Wrath on 3s lipo (11.1v) you must use a 16t pinion to avoid overheating the motor!!

Holmes Hobbies LLC

[Gomiband]

Originally Posted by Norton

How many cells were you running?
This is from Holmes page: IMPORTANT!! For use in the Axial Wrath on 3s lipo (11.1v) you must use a 16t pinion to avoid overheating the motor!!

2s. I was running really slow, testing the creep. Obviously paid the price.

[allanon1965]

Holmes can rebuild it pretty reasonably...get ahold of him....

[Eric0424]

Originally Posted by Gomiband

2s. I was running really slow, testing the creep. Obviously paid the price.

Ten minutes on 2S just creeping seems bit quick for it to give up the ghost.

I would check the drivetrain, pinion & spur mesh, etc. just as a precaution. The weight of the Wraith, 2.2" tires, added tire weights up front and high gears could have been enough, but it wouldn't hurt to check other ares for trouble.

[Natedog]

Originally Posted by Eric0424

It's probably beyond salvage, I've had a few of those myself.

If/when they get hot enough they can also melt the insulation on the windings.

Also noticed this on Holmes web site regarding the Crawl Master 540's.



Holmes Hobbies LLC

@OP, over geared and you killed the motor. 20/something (looks about 80T) is way too high for that motor. Buy new motor and gear as per HH recomendations.

[mikelshrum]

I had a 13turn crawlmaster do the same thing had a 87 spur and a 16 pinion on 3s on a pretty stock wraith no extra weight