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Old 01-20-2009, 11:50 PM   #1
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Default do lower turns motors give less less braking

Hi there
do lower turns motors give less less braking ??
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Old 01-21-2009, 03:03 AM   #2
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I don't know for a fact if they have less braking or not, but in a logical sense, if you are travelling faster, you ideally need more brake FETs and/or a stronger brake frequency to get the car to slow down or stop quicker.

This is why a lot of budget, low end ESC's cannot handle a modified motor, as the FETs are usually of a cheaper,inferior quality.

I don't understand motors enough to see why there would be less braking in a modified motor, with less windings for current to pass through, I would have thought they have more braking, as there is less distance for the current flow to negotiate.

But, logic never answers everything...
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Old 01-21-2009, 03:22 AM   #3
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The only motors I've noticed with significantly less braking are silver can 540s, mainly because they have such a weak magnetic field, and low brush friction.

All my race-spec motors have good braking, never been a problem slowing down on the track. Although personally I rarely use the brakes anyway!
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Old 01-21-2009, 09:27 AM   #4
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to me its related to gear ratio and torque...

lots of starting torque pretty much equates to lots of stopping torque
lower FDRs brake less than higher FDRs (for the same motor)

it seems to hold true for my experiences at least, but i am sure someone else can explain it correctly and with more explanation
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Old 01-21-2009, 03:01 PM   #5
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From experience the more powerful the motor, the stronger the brakes. Any spec motor I run needs the brakes dialed up to almost max to get the car to stop but mods you only need around 60% to stop quick.
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Old 01-22-2009, 12:55 AM   #6
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I don't know the answer either but my thoughts:

Assuming magnets and armatures are the same in the two motors

Less turns would have more braking cos less wire on armature = less resistance.

A motor that has more turns as we all know goes slower because it has more windings(wire) = more resistance so it needs more power to slow down.
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Old 01-22-2009, 01:19 AM   #7
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Quote:
Originally Posted by Dragonfire View Post
From experience the more powerful the motor, the stronger the brakes. Any spec motor I run needs the brakes dialed up to almost max to get the car to stop but mods you only need around 60% to stop quick.
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Old 01-22-2009, 02:22 AM   #8
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Quote:
Originally Posted by yeahyeah View Post
I don't know the answer either but my thoughts:

Assuming magnets and armatures are the same in the two motors

Less turns would have more braking cos less wire on armature = less resistance.

A motor that has more turns as we all know goes slower because it has more windings(wire) = more resistance so it needs more power to slow down.
Yes, I was thinking something like this, just wasnt too sure of the technical side to it... This is something I need to learn more about
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Old 01-22-2009, 04:30 AM   #9
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Quote:
Originally Posted by tc3team View Post
Yes, I was thinking something like this, just wasnt too sure of the technical side to it... This is something I need to learn more about
You will find its not just the brake power, but the way the brakes are delivered. Novak motors for instance tend to have very weak brakes until you dial them up to max. LRP motors have crazy braking at high speed but the brakes disappear as you slow down. SP/Orion tend to be a little soft up high but very linear mid to low.

You really need to try you motor out and adjust your settings to suit you driving lines.
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Old 01-22-2009, 05:03 AM   #10
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I mostly race in stock (27t) and have done primarily for quite some time, so I usually need little brakes in general, but thanks for the heads up

Sometimes I will put a 19t in and usually change the brake frequency, as with gearing I usually find that I am mostly with the right choice, and dont want to loose too much speed down the straight by gearing with a smaller pinion.

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Old 01-22-2009, 08:39 AM   #11
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on track, lower-turns motor will break better, because they can create more power. But if the gear ratio in a car is the same (5.5 an 13.5t for example), the 13.5 will break better (because of more torque)

But that all doesnt matter. Most ESC can adjust brake from verly low to extrem high. It just depends on your ESC setup.
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Old 01-22-2009, 10:11 AM   #12
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Quote:
Originally Posted by tc3team View Post
I mostly race in stock (27t) and have done primarily for quite some time, so I usually need little brakes in general, but thanks for the heads up

Sometimes I will put a 19t in and usually change the brake frequency, as with gearing I usually find that I am mostly with the right choice, and dont want to loose too much speed down the straight by gearing with a smaller pinion.

So much to learn, 15 years and still learning lots!...
I think the term for stock racing is 'brakes? what are they?'
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