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Old 11-05-2008, 09:31 PM   #1
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Default Brushless/Brushed number of turns

Is the number of turns on a Brushless motor equivalent to a brushed motor with the same number of turns?
eg Is a 10.5T brushless motor the same as a 10.5T brushed one?
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Old 11-05-2008, 09:59 PM   #2
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in terms of whats been approved for sanctioned racing..

27T brushed -- 17.5T brushless
19T brushed -- 10.5T brushless (or 13.5T brushless)

In general, the equivalent power levels are not the same when comparing the same number of winds on a brushed or brushless motor.
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Old 11-05-2008, 10:53 PM   #3
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19T brushed -- 10.5T brushless (or 13.5T brushless)
You've lost me now , how can a Brushless 10.5T or 13.5T equal a 19T brushed?....btw I'm not doubting you, just trying to make sense of it

I purchased a S400 and was told he'd give me a 10.5T brushed motor....so what would that equate to?

When people refer to what a class will run on, is Brushed/Brushless also specified...or are one of these the normal default so people know what they mean?
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Old 11-05-2008, 10:59 PM   #4
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The equivalencies are just rough guesses that were made by race organisers. As brushless motors develop, these guesses are being changed.

10.5 was the first guess at a 19T brushed equivalent, however it turns out that 10.5 is quite a lot faster, and that 13.5 (first made as a 27T equivalent) is closer.

If a wind in the rules is xx.5 then it will be brushless, round numbers are brushed.
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Old 11-05-2008, 11:39 PM   #5
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The 10.5T brushed motor is fast enough to run modified touring, although most would be opting for 5.5-3.5T brushless for this class.

The cutoff for Super Stock is 19T brushed.
Stock level racing is 27T brushed.

Hopefully you're aware that the lower the wind, the "faster" the motor is? Because basically with the 10.5T brushed, you've got a rocket coming your way and you're going to want to make sure you have some spare parts :P

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Old 11-06-2008, 02:15 AM   #6
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10t brushed is for Girls
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Old 11-06-2008, 03:32 AM   #7
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I read a note from someone who said "take brushed turns and halve them to get a similar performance brushless motor turn number".

So, that seems to work.

27T brushed -> 13.5 brushless
19T brushed -> 10.5 brushless
13T brushed -> 6.5 brushless
10T brushed -> 4.5 brushless

something like that. Brushless motors are not all the same - so the formula isn't exact - but works for a ballpark. Also note that brushless gearing is "way higher" than brushed in some cases. So, adding a few teeth on the pinion is typical when moving from brushed to brushless in the same "class".
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Old 11-06-2008, 07:10 PM   #8
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27T brushed -> 13.5 brushless
19T brushed -> 10.5 brushless
13T brushed -> 6.5 brushless
10T brushed -> 4.5 brushless

Also note that brushless gearing is "way higher" than brushed in some cases. So, adding a few teeth on the pinion is typical when moving from brushed to brushless in the same "class".
Why is that, if for example a 19T brushed is equivalent to 10.5 brushless. Is it because of extra torque?
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Old 11-06-2008, 11:24 PM   #9
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Quote:
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Why is that, if for example a 19T brushed is equivalent to 10.5 brushless. Is it because of extra torque?
You are reading too much into the turns. Brushless motors have a completely different construction.
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Old 11-07-2008, 12:05 AM   #10
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Quote:
Originally Posted by jmcvicker View Post
I read a note from someone who said "take brushed turns and halve them to get a similar performance brushless motor turn number".

So, that seems to work.

27T brushed -> 13.5 brushless
19T brushed -> 10.5 brushless
13T brushed -> 6.5 brushless
10T brushed -> 4.5 brushless

something like that. Brushless motors are not all the same - so the formula isn't exact - but works for a ballpark. Also note that brushless gearing is "way higher" than brushed in some cases. So, adding a few teeth on the pinion is typical when moving from brushed to brushless in the same "class".

That's a good "rule of thumb" but in reality, your list could be offset by one


27T brushed -> 17.5 brushless
19T brushed -> 13.5 brushless
13T brushed -> 10.5 brushless
10T brushed -> 6.5 brushless
7T brushed -> 3.5 brushless

going from 27t brushed to 13.5 brushless was a huge leap in gearing for me at my local track. I went from 8.2 down to 5.1
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Old 11-07-2008, 07:49 AM   #11
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I heard it was like brushless X2 -2. So a 13.5 would be more to a 25T motor speed. It just seems much faster because you can gear the hell out of them. Try run a 13.5 vs a 19 turn with the same gearing. 19T will be faster.
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Old 11-07-2008, 08:13 AM   #12
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Obviously you wouldn't run the same gearing because brushless has a much different torque curve and rpm. Brushless has less rpm and more torque for the same power output. Therefore the gearing must be longer.

But if both 13.5 and 19T are geared properly, they should both run competitive and that's what matters...
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Old 11-07-2008, 08:24 AM   #13
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I guess you can compare them as BL= V8, Brushed = 4cyl turbo engine.
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Old 11-07-2008, 07:52 PM   #14
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correct me if i am wrong. i always thought it was the rpm of the motor that determinds the brushed/brushless equivalency. 25000rpm motor on brushed= 27t or 17.5 brushless.
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Old 11-20-2008, 06:02 AM   #15
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hi all....
i'm new to this brushless thingy...
brand such as Mamba,HSP,HL is using KV as rating for their brushless motor
how to compare wit other brand?
they rate thier brushless motor using 3000KV,5000KV,7000KV
as the rating .. what is the equivelent ?

3000KV = ?T ( other Brushless Motor ) = ?T ( Brush Motor )
5000KV = ?
7000KV = ?

can someone enlighten me?
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