# 5800 shattered



## SantozRey (Apr 17, 2005)

Has anyone ever shattered the rotor in a brushless motor? In specific a Novak 5800... I don't know how I did it but it's shattered. I've got it installed in a Stampede geared 15/87. I think it might of been from a short cartwheel, but it wasn't that bad of a crash.


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## kevinm (Jan 16, 2002)

I've seen a few shattered rotors, mostly (if not all) from motors that got too hot. Temperatures above 175°F can cause this. The most common problem I've seen with the 5800 is a rotor that slips on the shaft. The new replacement rotors are supposed to be more durable.


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## ta_man (Apr 10, 2005)

If you read between the lines regarding the new "sintered" rotor in the GTB 3.5 you get the impression that the 5800 rotor is just held together with epoxy. [A.K.A. plastic]. (At least that's what I get from reading between the lines.) So that might be why they:

a) have a 175 degree limit
b) can end up slipping on the shaft
c) can shatter if you get them too hot

This is pitiful!


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## SantozRey (Apr 17, 2005)

Well.... ain't that nice. thanx ta man! ....the rotor diffinately is NOT a solid magnet.
I already emailed Novak YESTERDAY, hopefully I will get a positive response from them... saying they can replace it!


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## EAMotorsports (Sep 25, 2001)

ta_man said:


> If you read between the lines regarding the new "sintered" rotor in the GTB 3.5 you get the impression that the 5800 rotor is just held together with epoxy. [A.K.A. plastic]. (At least that's what I get from reading between the lines.) So that might be why they:
> 
> a) have a 175 degree limit
> b) can end up slipping on the shaft
> ...


 Roar rules only allowed for a bonded magnet as of last year for all brushless motors. When the rules were written Sintered magnets were around 4-5 times more expensive. Since then sintered magnets have come down to almost the exact same price as bonded. 

The difference between bonded and sintered are:
Bonded magnets are 50% neodynium and 50% epoxy.
Sintered magnets are around 95% neodynium and then the material that holds them together...not epoxy. The sintered magnets give the motor about another 150 degree operating temp range and also give more power, less heat, and more eff.

At least this is what I have been told. Next year everything may be sintered!!

EA


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## muddd (Sep 7, 2005)

EA, how do i know if i got sintered or bonded magnets, is it on the box, mayb this means nothing but mine is a 4300, and it says neodymium magnets but doesnt say bonded or sintered ,,,,,thx


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## EAMotorsports (Sep 25, 2001)

muddd said:


> EA, how do i know if i got sintered or bonded magnets, is it on the box, mayb this means nothing but mine is a 4300, and it says neodymium magnets but doesnt say bonded or sintered ,,,,,thx


 The ONLY motor novak sells right now that comes with a sintered magnet rotor is the 3.5. All others are bonded. 

EA


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## muddd (Sep 7, 2005)

thanks man, i was thinkin i needed a new motor, well ihope to get my speedo problems under control, if i hav a older motor, it says on the box for use only with novak brushless speed controls, could this maybe be why im havn such a problem with my lrp shuttn down, do i need a newer motor, i know this isnt the spot for it but oh well,thx


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## Z-Main Loser (Nov 17, 2004)

Mudd, I think the reason it says that on the card is so that you buy their speedo. When did you get the motor? There shouldn't be a problem using any motor with the GTB or LRP as long as its a sensored motor.


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## EAMotorsports (Sep 25, 2001)

muddd said:


> thanks man, i was thinkin i needed a new motor, well ihope to get my speedo problems under control, if i hav a older motor, it says on the box for use only with novak brushless speed controls, could this maybe be why im havn such a problem with my lrp shuttn down, do i need a newer motor, i know this isnt the spot for it but oh well,thx


 Did you make sure your not operating in the Lipo mode? I dont know much about Brushless stuff yet...but am working on it. I know someone on here had that problem before and their speedo was in Lipo mode so as soon as the peak came off the batteries it was shutting down.

EA


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