View Full Version : Questions about brushless motors

01-03-2007, 12:15 AM

I'm very very new to the electric RC world. :confused: Can someone tell me the difference between regular motors and brushless motors? I hear a lot of people discussing buying or upgrading to a brushless motor... what are the advantages?

Thanks and happy flying!

01-03-2007, 01:56 AM
Brushed motors use carbon brushes that rub on the commutator (I think that is the right word) shaft and will eventaully wear out. A brushless motor is just that, no brushes to wear out. You can spot the difference a mile away as the brushed motors use 2 wires and the brushless use 3. Different ESC's are required for each.

The major difference is they generally produce more power!

01-03-2007, 03:17 AM
Brushed motors used to be more common too. That may not be the case these days, although a lot of planes still come with a brushed motor. Generally a brushless motor is more efficient than a brushed as well. So like Bill said, you have more power with a brushless motor of comparable size as compared to a brushed motor. This also usually translates to longer flight times.

01-03-2007, 03:19 AM
Tinman, do a google search for ''how stuff works''....its a great site for explanation of thousands of things and phenomena. Once there, search for electgric motors and you will find a great deal of info showing parts, theory and much more.

i love that site.



01-03-2007, 05:05 PM
Thanks Tim,

I'll check put that website. Sounds cool, I'll probably be up all night reading about stuff!


01-03-2007, 08:16 PM
be careful with HowStuffWorks.com.... I got one there once and didn't stop reading for days. :) I still go back there just to see whats new. Very cool site.

01-03-2007, 08:19 PM
that happens to me here!:eek:

01-03-2007, 10:46 PM
Wow I should of never gone to that webpage! I've been on it for two hours straight here at work!! haha very interesting!!!

01-03-2007, 11:21 PM
Im still on there, wow I can feel my brain getting bigger! I feel really smart! My eyes kinda hurt though...

01-04-2007, 02:14 AM
I'm with you Tinman, that is a dangerous website. I was on it for several hours at work today too.


01-04-2007, 03:08 PM
Glad im not the only one :)

01-04-2007, 04:21 PM

Animations and simulations of brushless motors:
www.rcgroups.com/forums/showthread.php?t=216928 (http://www.rcgroups.com/forums/showthread.php?t=216928)

Vriendelijke groeten ;) Ron
• diy motor building tips & tricks (http://www.rcgroups.com/forums/showthread.php?t=240993)
• diy brushless motor discussion group (http://www.yahoogroups.com/group/lrk-torquemax)
• Drive Calculator (http://www.yahoogroups.com/group/D-calc/) download & discussion group
• int. E fly-in & diy outrunner meet (http://home.hetnet.nl/%7Eronvans/), Aug.26 2007, Nijmegen, the Netherlands

01-04-2007, 04:48 PM
Thanks Ron I'll check that out.

01-04-2007, 07:02 PM
... I'm very very new to the electric RC world ...Have a look at this e-flight FAQ:

Vriendelijke groeten ;) Ron

01-29-2007, 07:57 AM
i'm in need of help. i've got a ST Model motor, its a 2212 model with 1250kv. its an outrunner and i'm wondering...how can i work out how many watts it is or produces, i have a 8x6 prop on it atm, thanks

01-29-2007, 02:12 PM
to determine output wattage, measure the current draw with a multimeter while it's running at full throttle. then multiply the # of amps X your voltage. the result is your INPUT watts - remember, not all the energy put INTO the motor is applied directly to the prop due to losses from resistance, friction, core losses, etc. If you know your motor's efficiency (I wouldn't necessarily trust the mfr's claimed eff rating) you can multiply your INPUT watts X the efficiency (%) = OUTPUT watts.

02-01-2007, 08:09 AM
thanks , i'll have to get a multimeter i guess :P

Dr Kiwi
02-01-2007, 05:49 PM
Be careful with an 8x6 on a 1250Kv motor - that might be drawing 15-20A.