Understanding motor turns

[JohnRobHolmes]

lower KV = higher turns. brushed or brushless.

Torque is affected in brushed motors as they get faster, right around the 2500kv mark it becomes evident that brush losses begin to dominate the power curve and brush wear accelerates greatly. You might notice we don't offer brushed motors faster than this, only as custom motors when customers are educated on the downsides.


Torque is not affected in brushless motors when KV changes. Controller losses do increase as KV increases in the motor, but it causes only minute amounts of torque loss unless the controller temperature increases greatly. If higher KV is used AND geared down low enough to meet the wheelspeed of a lower KV choice, you will have more torque at the wheel, more power on tap, better low speed control, and better drag brake. There is no reason to buy a KV that is slower than wanted, but if there is geardown available it is wise to choose a higher KV and gear the vehicle down to suit.


I would recommend 3300kv minimum. 3500 to 4500kv would be more suitable for 25mph in something like a bomber or wraith. The Puller Pro 540 in 3500kv is most popular for general use, and the 4500kv for rock racing.

[Ditchrat]

Originally Posted by cwhfsr

In continuing the zombie thread (great find BTW). How does KV fit into this mix? Seems like for brushless people are saying to get 3300kv or 3500kv or whatever. How does that compare to the turns?

Thanks!

Kv(as in v subscript) is rpm per volt. Not to be confused with kV which is kilovolts.

Unloaded Kv x input voltage = nominal rpms

So you can calculate that out for a brushless then compare the nominal rpms of the two motors. Since the voltage in can be a variable you can also use this to calculate the difference between a 2s and 3s battery.

[rcwolf]

just watch this has everything explained in understandable English..LOL https://www.youtube.com/watch?v=yjbc3PMKyGk

[Summitbasher90]

Zombie still alive in 2017!!! Lol

I have been noticing my stock motor getting weaking in my stock deadbolt and want to upgrade motor and esc. Im lookin at the holms hobby 35t but still have some questions. Whats with the 35t torque mater pro vs the 35t torque master expert. And further than that whats the difference in the straght leads vs the 90* leads and whats it mean by motor timing? And as for the esc, not sure wich one to get. I run on 2s and its mosly trailing with moderate crawling here in florida.

Man i feel like such a newb. When it comes to going fast with brushless i know exactly what i need. Who figured slow would be so complicated? Lol

[notajerryskid]

Originally Posted by lidebt2

brushless motors

sintered rotor motors
21.5 - slowest motor (comparable to a 55 turn lathe or crawler motor)
18.5 - similar to a 45 or 35 turn lathe or crawler motor
17.5 - very close to a 27 turn stock motor
13.5 - slightly faster than a 27 turn stock motor
10.5 - slightly faster than a 19 turn motor
8.5 - 13-15 turn motor
7.5 - 11-12 turn motor
6.5 - 10-11 turn motor
5.5 - 9-10 turn motor
4.5 - 8-9 turn motor
3.5 - 7-6 turn motor

bonded rotor motors
ex13.5 - close to a 27 turn stock motor
ss4300 = ex10.5 - close to a 19 turn motor
ss5800 = ex8.5 - 15-17 turn motor


brushed motors

55 turn = slow

7 turn = fast

machine wound = done by a machine (cheaper motor)

hand wound = done by a person (expensive)

thank you!!!

[Hazel0ne]

Thanks for sharing

[Eluder]

I know this is a old thread that was rehashed and forgotten but I wanted to give it a bump as it has been the most helpful for me in starting to understand what the the different motor turns are for...

[LincolnofDeath]

2X for me, an old dork and newb crawler... have searched high and low and this popping up here catches me up to quality zombie-vintage 2010. Totally succinct description and to the point, especially having bought a used Torquemaster Expert 35T (540) to try in an Element Sendero. Thanks for your continued patience with us new guys whilst we search waaaay back for the unconscious knowledge.
Now I’ll save this question for a new thread, but it’s, “Can the armature of a 35T be swapped with, say, a 27T or 21T armature of the same size can?” (EDIT: THE ANSWER TO THIS IS YES AND THEY ARE SOLD ON HH WEBSITE). I’ve been looking for a couple days now and learned many things but not this specific question. I’ll go post it now.
Peace!

[upit4x4]

Originally Posted by JohnRobHolmes

lower KV = higher turns. brushed or brushless.

Torque is affected in brushed motors as they get faster, right around the 2500kv mark it becomes evident that brush losses begin to dominate the power curve and brush wear accelerates greatly. You might notice we don't offer brushed motors faster than this, only as custom motors when customers are educated on the downsides.


Torque is not affected in brushless motors when KV changes. Controller losses do increase as KV increases in the motor, but it causes only minute amounts of torque loss unless the controller temperature increases greatly. If higher KV is used AND geared down low enough to meet the wheelspeed of a lower KV choice, you will have more torque at the wheel, more power on tap, better low speed control, and better drag brake. There is no reason to buy a KV that is slower than wanted, but if there is geardown available it is wise to choose a higher KV and gear the vehicle down to suit.


I would recommend 3300kv minimum. 3500 to 4500kv would be more suitable for 25mph in something like a bomber or wraith. The Puller Pro 540 in 3500kv is most popular for general use, and the 4500kv for rock racing.

Would this recommendation change if you include the 2 speed option ?

[JohnRobHolmes]

Originally Posted by upit4x4

Would this recommendation change if you include the 2 speed option ?

You can use a lower Kv with a two speed and still get a wide wheelspeed range. For two speed rigs I typically choose a 2200 or 2700kv, when I would have normally chosen 3500kv for single speed in the same use.