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Going Brushless
Brushless Motors and Speed Controls

What's all the fuss about?
Back when I re-entered RC a couple years ago, in my mind brushless motors were really for the hard core guys out on the cutting edge of upgrading. They were the serious nerds picking this non-mainstream controller and pairing it with an even less know brushless motor and were on their own to make it work.  They were the Rich nerds at that RC nerds, because it was very expensive to put together a brushless system.  All that has changed in the last couple of years.  Relatively speaking brushless motor systems are not that expensive any more in today's market of $150+ ESCs and $50+ motors.  Mainstream manufacturers such as Novak and Castle have plug and play systems with outstanding support to pack them up.

I personally am a big fan and love my Novak Velociti GTB brushless system and my Castle Creation Mamba Max systems, but I was skeptical at first simply because there isn't a lot of info out there on the subject of brushless motors and which one to choose. I hope I can lay out some ideas, concepts, and information so that you can begin to enjoy all that brushless systems have to offer.  The big things to know, almost no maintenance, huge speeds, monster torque, and extreme durability and literally no down side.  Now that I have your interest, read on.

What are they?
There are basically two options of brushless systems, "plug and play" and "component systems." Like your current brushed system, brushless systems have a motor and a speed control (called a controller on brushless systems).  The difference between the two systems is more how the power moves through the controller to the motor and how the motor is made to respond to those inputs, but put simply there still needs to be a battery, a speed controller, and a motor just like your brushed motor setup.

The "Plug and Play" systems from companies such as Novak, Castle Creations, and others are just that, drop them in, plug in a battery, program and go.  The "Component" systems will include a motor from this manufacturer, and controller from that manufacturer and it's up to you to figure out how to make it work.  Generally the Component systems produce much higher power outputs and speeds, but take a more expertise to get working. 

Brushless System Types
There are also two types of brushless systems, sensored and sensorless.  The sensored motors (almost exclusively from Novak) provide the advantage of extremely precise movements at very low RPMs and delivery a silky smooth non-peaky power band.  Sensored motors can be recognized from the extra bundle of control wires coming out of the motor to the ESC on top of the three main power wires.  Generally the Sensored motors are limited to one stated input voltage range such as 6 cell 7.2V or 12 cell 14.4V. 

Sensorless motors utilize only the three power wires to control the motor.  Generally the sensorless motor systems are less precise and deliver a peakier less smooth power band, but can handle huge voltage inputs  ranges such as being able to handle everything from 4.8V-14.4V all on one system. 

The brushless Sensored systems are getting better and better every year and may soon delivery the smooth power delivery of the Sensored systems.  The battle is still raging which is a better system as both have there advantages and disadvantages. 

Why do you want/need a brushless motor and controller?
It may be that you want to get lots of extra speed and torque.  You also may have grown tired of replacing motors and fiddling with the Commutators, brushes and springs on your "brushed" motors.  Or you have heard that the investment in a brushless system pays big dividends with lower cost, long term durability, fun, and less upkeep.  It may also be that you are sick and tired of the upkeep of your nitro car and are wanting to convert it to a simple brushless system like a lot of people are doing now.  All of these are great reasons.

Brushless motors and controller systems combine all the best qualities of the other propulsion systems. They have the noiseless operation, convenience, torque, and simplicity of electrics with the big top speed capabilities of nitro. The biggy here is the amazing torque and speed that comes from even a less expensive brushless system.  Most people see at least high 30-40 MPH with good quality batteries - this is plenty fast for 99.9% of us.  The torque is also simply amazing.  Some of the newer plug and play systems out there indicate speeds of 50+MPH are easily attainable with a 3s lithium polymer battery (the equivalent of a 9 cell battery pack). 

Most of the brushless systems put you in biting and eating range of all but the fastest nitro cars.  The fastest and most expensive brushless systems can and do outrun and out perform top nitro vehicles.  The fastest RC's according to Guinness are brushless powered vehicles and are in the 135-140MPH range - yes that's just nuts.

It's also a pretty simple system, battery, brushless controller, and motor, install and go - and that's one reason everyone loves the simplicity of electric R/Cs.  Another is flexibility, most of the brushless systems allow you to tune the performance of the system by changing the setting of the controller.  Some manufacturers controllers can be programmed and tuned via a PC interface.

There are now a large number of people converting nitro R/Cs to brushless due to noise, performance, personal, convenience, or speed goals.  In the end these people will almost always say that they will never go back to nitro and that brushless motors are the pinnacle of RC power systems.

What do they cost?
That's a big broad question.  Let's say it's in a car like a Rustler for example.  A great refurbished system like the Novak 5800SS runs about $160 directly from Novak and even comes with a full warranty.  Now that is a pretty versatile system that is just at home in a 1/10 scale buggy all the way to something like a Traxxas Stampede.  Unfortunately they go up pretty quick after that.  Sticking to the "plug and play" systems, Novak's ROAR approved new Velociti series will take $230 out of your back pocket and Castle Creations has the VERY impressive and equally pricey system Mamba Max that promises 50+MPH speeds. 

Less known names heard mentioned on occasion include Hacker and MGM and others can get into the $200 price range for just the motor with the controllers ranging from $200-$500+ that delivery potentially record setting performance. 

Most ready to run motor and controller systems and component (i.e. you buy them separately sometimes from different manufacturers) start in the $160 range and go to about $250.  Other very high performance systems and component sets can easily hit $1000 for a top of the market offering. 

Are they worth the money?
Every penny.  The mainstream systems from Novak, LRP, Orion, and Castle Creations offer up more performance than most people are ready for all in an easy plug and play package.  The more advanced systems like those offered from Hacker or others you better be a damn good driver (a really really damn good driver) because these things produce absolutely sick ugly amounts of torque and speed, the likes of which most electric cars' transmission systems cannot handle without some modification.

Seems like a lot of money doesn't it? Well it may be up front, but in just a year, a regular under $250 system can pay for itself.  No brush replacements, no Commutator cutting, no motor replacements, and most of all NO maintenance.  I look at it this way, a good ESC is $80+, then you need a couple motors, one for the track on one for bashing $30-50 each on those.  Within that year you will also need at least one set of new brushes, probably a Commutator cut, and possibly even a motor replacement or two.  All of a sudden that $160 is an easy decision and you are already looking at the more expensive brushless systems making the justification that it really isn't that expensive. 

Due to the clay sandy soil out here in Nebraska, I was chewing through motors left and right (uhh that and my tendency to slightly over gear a motor that was already on it's last legs). The Brushless motors are sealed so that junk can't get in there to tear things up and are so powerful you will usually gear down to slow things down a bit. For me the Novak GTB 4.5R system paid off big time in a hurry.

How do Brushless Motors Work?

Contrary to popular opinion, brushless motors were not an RC related invention, rather developed for commercial industrial applications where a motor run continuously (sometimes 24/7 - think mail sorting machine). Basically the whole design is more efficient, can achieve a higher RPM, has more power/torque, and can do it for long extended periods of time without fatigue. Just what is needed for R/Cs.

A brushless motor is basically backward compared to a standard brushed motor. On a brushed or stock motor the windings are on the armature/shaft and the magnets are mounted to the can.  On a brushless motor the windings are glued to the inside of the can, and the permanent magnets are bonded to the rotor. Because the wires don't move, you don't need the brushes to transfer the electricity over the armature and in turn through the windings.

A sensorless motor requires a sensorless controller, and a vise versa a sensored motor requires a sensored controller - never fear that is usually prominently posted.

Sensored motor systems keep track of the exact position of the rotor at all times so the controller can delivery that silky smooth precise power and great feel even at super low RPMs.  On a Sensorless motor system the controller kind of suggests the motor go forward or backward, less precise but adds the flexibility of being able to run a wide voltage input range without fear of burning up delicate sensors.  This less than smooth power delivery on older or cheaper brushless systems is called cogging or occasionally incorrectly identified as glitching.

If that isn't geaky or in depth enough, do an online search of the topic and I am sure you will find an abundance of info.

Nitro to Brushless conversion - I think this story applies here -
A little story about a track session a couple weeks ago.

I was up at the track, there was this guy with this beautiful brand new $800 Truggy, a guy I know knew as a racer and knew that he knows his stuff. Problem was that while all of us electrics overtook the track, this guy spent the better part of an hour attempting to start then keep running his new truggy. I see this a lot, guys at parks spending more time attempting to start, keep there gas rigs running and tuned properly. Meantime we electric folks already have been bashing for 30 minutes or more. Then there is the noise thing that ticks everyone off. Electrics = insert charged battery and go.

My point of the story is that this exact scenario is the reason that many many RC'ers such as this guy are converting gas cars to brushless.  Yes they are tearing out all that nitro stuff and replacing the gas motor with a brushless system.  Gas cars are fun initially but can be kind of a pain in the butt and can severely cut down on the fun time of the hobby for those of us who just want to have fun - just my two cents.

So what should you get?

It used to be not that long ago, that the only brushless systems available were fairly obscure and hard to fine RC helicopter motors. These were not exactly made for ground travel and were crazy expensive.  Today getting into the non-mainstream manufacturers is still lacks a lot of "how to", they have become more and more approachable but still a little hard to figure out.  Brushless systems manufacturers like Hacker, MGM, Mtroniks (which I have had horrible experiences with), Quark and others will definitely provide huge performance gains over the Novak and LRP systems, but these systems are definitely not plug and play and can (I want to emphasize "can") bring their own set of challenges from a support perspective.  The expectation is that you already know how to pair up brushless sensorless motors with brushless sensorless controllers with your input voltage capabilities all while keeping in mind that too much power will simply tear your car apart from toque and to little will make it perform less than expected.

Batteries and Current Considerations
A huge consideration is the quality, type, and capacity of the battery.  Let's say you understand a garbage battery compared to something like a Trinity, GP, IB, or Sanyo and that you understand battery capacities 1500Mh, 3300Mh, 4400Mh and the like.  You may also know that there is a difference between NiMH, NiCad, and the new high current LiPo (Lithium/Polymer) batteries. 

What you probably don't know is that a GP3300 fully charged in a Stampede running a 4.5R GTB wide open off road will last about 7-10 Minutes if you are lucky, with a IB4400 about 10-15 until full discharge.  The motor is over stressing itself and is drawing tons of current in the process simply because the fact the motor is attempting to hit supersonic speeds on speed limiting terrain with gearing that is still on the high side even at 12/87.  Those same batteries in the Stampede with a 7.5R GTB and you are looking at nearly double the run times and still about the same speeds off road.

Something you have to consider is that the brushless systems are huge current hogs and can drain a battery in a few minutes.  After all they are spinning at nearly double the RPM with nearly double the power of a comparable brushed motor.  Before you even think the question - yes you will need the best batteries you can afford at the very least Radio Shack GP3300s.

You should also consider that although a 4.5R in your Stampede would be nice, but not the best choice from a battery discharge perspective, you should consider a 7.5R or 6.5R for the Stampede and leave the 4.5R and new 3.5R for the touring cars or at least the high speed on road RC's.  On 6 cells, a Castle Mamba Max 4600 would provide all the power you will ever need in a Stampede, the 4600 or 5700 for something like the Rustler/Bandit and the 7700 for road racing or road tuned stadium trucks.  Honestly your biggest problem will be keeping the tires from flying off the rims and having enough batteries to make it through an hour or so.

Considerations and Kv Explained
You will see the term Kv referenced on brushless motors (both sensored and sensorless).  Kv or the less geeky translation RPM/Volt, tells you how fast the motor without a load will spin per volt applied.  As an example the Novak 4.5R rating is 9000 RPM/Volt which translates to 64,800 RPM with a standard 7.2 volt 6 cell pack input.  Keeping in mind that is a no-load figure and will be significantly less depending on your vehicle dependant on gearing, tire size, internal transmission friction, battery quality, controller, ...etc.  That figure also indicates how much torque the motor will generate.  The smaller the number the more torque, the bigger the number the faster the motor will spin.  Its really about where do you want the power used, do you want it for speed or torque. The key is finding the balance between speed and torque for your vehicle. 

Although I did it and think any more torque and speed and the Stampede would be un-drivable, 4.5R is probably a little to fast for a Stampede and makes most of it's power at a higher RPM and requires me to gear 12/87 with no place to go should I want to gear down a little more. Likewise Novak's super torquey brushless Crawler motor with a 2700 RPM/Volt rating is to slow and doesn't have the higher RPM to produce the higher speeds and would probably require some crazy gearing like 26/78 to make it hit a decent speed. 

Probably the most flexible systems for 1/10th scale R/Cs are in the 4500-6500 Kv range and allow more flexible gearing for a broader range of driving conditions and provide improved drive times over higher RPM motors.  A 1/10th scale brushless system in this range will work well for almost any buggy, stadium truck or the likes of the Stampede.   Keeping in mind my experiment with a brushed 550 low RPM and high torque Monster Maxx motor on the Ultra-Rusty, you can always gear up with a low torque motor and sometimes it will be faster than a high RPM motor.

Plug and Play systems that fall into this category are the Novak SS5800 motor controller combo and Velociti 7.5R, 6.5R, and 5.5R motors with the GTB controller.  Castle Creations' Mamba Max 4600, 5700, or 7700 systems are also great choices that will drive your buggy or stadium truck at warp speed.  Touring cars small tires and higher RPM requirements need the higher Kv brushless systems such as the Novak 3.5R or 4.5R Systems, or any of Castle's Mamba Max systems.  Orion has some pretty nice systems as well as LRP. 

For Component (build-your-own) brushless systems, I recommend buying the most powerful controller you can afford - the Castle Creations Mamba Max Controller is highly recommended.  The general thought is that a cheap brushless motor is a good deal but a cheap controller is not. I disagree, some testing information shared with me by Castle Creations showed that all brushless motors were not created equal and a big reason they enlisted the assistance of a customer brushless motor builder, instead of rebranding and existing and available motor.  A good sensorless controller is the Mamba Max and can handle just about any sensorless motor you throw at it and provides all the tuning your heart will every desire with included PC interface and software and will drive even the most powerful sensorless motors with ease and is located in Kansas City.  With very few exceptions you can run any sensorless controller with any motor just like brushed but specs should be matched up to assure best performance. There are vary few exceptions so assure you check with the vendor for controller/motor compatibility. 

Brushless Systems Reference Resources
*My apologies to everyone I lifted this info from, I had a little server error and lost the links to the sources.

Novak - Plug and Play, excellent support, priced competitively, and offer re-manufactured units at a big discount.  They make a variety of plug and play systems including their newest dual purpose GTB brushless/brushed controller and their Velociti series motors.

Castle Creations This company is the reason that brushless is what it is. Headquartered in Kansas they make everything here in the states. Castle makes the Mamba Max Controller and has packages that include it's 4600, 5700, and 7700kv brushless motors in a plug and play system.

Hacker brushless Hacker of Germany is great stuff according everything I have read and now have a US distributor. Just look over the specs carefully. Like every other system out there the fastest motor is not necessarily the right one for your project.

Neumotors.com Neu Motors, simply the best and can do custom windings. They are said to make the best motors and the specs are conservative and accurate. The rpm is exact and the wattage is underrated, so you get more than they say. This company is American.

ICare-RC Plettenberg a very close second to Neu. Icare RC is the American importer and even their web site leaves a lot to be desired on the Plettenberg side. Best to call them most likely to avoid confusion. Also German made.

Finedesign RC  Chris Fine is one great designer and a real thinker. If you check out his site you will find a great assortment of brushless motors and controllers recommendations.

Mgm-compro  Make sure that you check the British flag in the upper right corner or you will get the site that is in Check.