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Old 12-20-2008, 06:36 PM   #1
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Default do brushless motors lose performance over time?

I tried doing a search first, however could not find what I was looking for.

Do brushless motors deteriorate over time?

I'm thinking of buying 2nd hand brushless motors rather than new ones.
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Old 12-20-2008, 06:44 PM   #2
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they can lose some performance overtime... but the last a loooonnnggg time!
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Old 12-20-2008, 07:31 PM   #3
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If they over heat they loose performance or if they have out dated internals they will lose performance
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Old 12-20-2008, 07:32 PM   #4
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the bearings can go, so check to see if there crunchy. The rotor is a magnet, and magnets can loose there strength over time and when exposed to heat. that being said, the symptoms would be a less torquey motor that runs a bit hotter, which would be impossible to diagnose.

generally if it runs, its ok.
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Old 12-20-2008, 07:41 PM   #5
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The thing you want to avoid are ones that have been run hot. You can run a brushless, not really knowing what you're doing and get it so hot that you demag the magnet and it's finished. Heat is also hard on the brgs.

Avoid anything that looks like its been hot. Check how well it spins - its its nor smmoth, I wouldn't consider it. I've had mixed results with used - 50%, one was good the other was short lived and didn't last a month. I buy new unless its someone I know or get to try it or see it run 1st.
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Old 12-20-2008, 09:07 PM   #6
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i had a bearing on my BL motor totally seized. it got really hot and caused the speedie to thermal. i thought it was a terminal failure but after a quick bearing swop, everything was good to go

if the rotor is the magnet, does that mean a rotor replacement = new lease of life? equivalent to replacing the brushed motor comm?
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Old 12-20-2008, 10:13 PM   #7
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I really wouldn't worry about heat on a brushless. Has your brushless motor ever gotten weaker or slower after an extended run where it got really hot? None of mine have!! A sintered neodymium rotor has to get pretty hot--hotter than you would run a motor even in summer under a big load to lose any appreciable magnet strength. A bonded rotor might start falling apart but a good sintered heat really isn't an issue.

Keep fresh bearings in the motor and in theory you shouldn't lose any strength. The resistance in the windings shouldn't change.
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Old 12-21-2008, 06:16 AM   #8
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Quote:
Originally Posted by wyl03 View Post
if the rotor is the magnet, does that mean a rotor replacement = new lease of life? equivalent to replacing the brushed motor comm?
Yes and not. New rotor helps to bring new life to motor if winds in can aren't damaged. And it's not completely equivalent to replacing comm in brushed motor - in brushed motor magnets degrade faster and you can't change them, more equivalent is comm change and magnets zap - but that's almost new motor
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Old 12-21-2008, 07:36 AM   #9
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my question is??how much life are u guys getting out of a bl motor??1 yr,2 yrs etc??
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Old 12-21-2008, 07:44 AM   #10
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I've been running the same 13.5 for over a year and I haven't seen any drop off yet
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Old 12-21-2008, 07:59 AM   #11
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Quote:
Originally Posted by abailey21 View Post
I've been running the same 13.5 for over a year and I haven't seen any drop off yet
thats what i wanted to here. def worth the investment
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Old 12-21-2008, 08:06 AM   #12
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I'm going on my 2nd year . I'm just now looking for a differn't motor.
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Old 12-21-2008, 08:31 AM   #13
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Since we're at this topic,
is it a good idea to pull out the rotor for cleaning? Will it affect the magnetism or something?
With all the off-road we ran, and my motor being a Orion (with open ventilation slots), I believe quite a bit of dust will be trapped inside the motor.

Also, just want to find out how often you guys clean n lube the bearings?
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Old 12-21-2008, 09:40 AM   #14
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How hot is too hot? 180F?
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Old 12-21-2008, 07:27 PM   #15
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I've been running a novak 13.5 for over two years, replaced the bearings, and a sintered rotor. Still fast enough for a small carpet offroad track.
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