The Brushless Motor Advantage

When it comes to selecting the 'power plant' of your AEG replica, the motor is the component that does all the heavy lifting. Outside of hop up modifications, it is also the one upgrade where you can noticeably feel a distinct improvement in performance, as opposed to more passive improvements such as pistons, cylinder heads and so forth.

Until recently, upgraded motors primarily relied on Neodymium magnet technology, and were still using a classic brushed design. While decently reliable and well-proven, brushes do wear out over time and need to be replaced as it is a consumable part. As brushes wear, this also creates carbon deposits and a fine accumulation of powdery debris inside the motor and grip of the gun. This will gradually degrade the performance of the motor, and in seriously fouled conditions, might even permit it from functioning altogether if the brushes are overly worn or are unable to make complete contact with the commutator.

Radio Controlled (RC) hobby sports have long enjoyed the advantages of brushless motor technology, but it has only been within the last few years that brushless motors have become commonplace in Airsoft. Owing to their many advantages, you can expect to see this technology flourish and become more commonplace in the market. I would even expect some higher-end manufacturers to adopt it as their OEM motor on new models.

Most of the higher-tier builds I offer will be equipped with a Warhead brand brushless motor. More specifically I prefer the 30K standard torque model as it has the best efficiency-to-cost ratio. While Warhead offers higher speed variants and an even more extravagant (and expensive) "Ronin" version, the 30K variant hits all the ideal check marks; having better efficiency than the high speed versions and the lower-cost Base models, and also being compatible with a wide variety of gear ratios at very minimal cost to efficiency. The desired Rate-Of-Fire can be controlled through gear ratio, and this typically only changes the associated amperage draw by single digits.

Warhead themselves also have an excellent warranty policy and are continuously improving the design of the motor, as well as offering timely support for any issues or questions one might have. I personally use Warhead brushless motors in all of my personal builds that can accept them, some of which are have been operated in excess of several hundred thousands of rounds.

But what does "efficiency" mean really?

• Greatly reduced battery consumption
• Cooler operating temperature - especially under sustained use

As you can see from the below charts, the Warhead has substantially better efficiency than many popular brushed motor designs.

Heat Kills

If you've been playing Airsoft for any length of time, you're probably well familiar with having the motor grip on your rifle start to get warm, or even boiling hot if you've been really heavy on the trigger. You might have even noticed your batteries getting a little toasty, even. The quality of setup - gear shimming, resistance, motor type and gear ratio used can greatly affect how soon and how hot your setup might run. Poorly configured builds will get hot rather quickly, whereas better-built setups will remain cooler for longer. Mixing high-speed gears with high-speed motors is a good recipe for slow-cooking your battery, as an example.

Keep in mind that certain activities will increase heat generation more than others too. Shooting in semi-auto mode typically pulls about 1/3 to 1/2 as many more amps as shooting in full auto does. Even though it is slightly more efficient, long strings of continuous full auto fire or "mag dumps" will ultimately generate heat too. Binary trigger modes and use of Active Braking, which are features commonly found on MOSFET's and ETU's can generate a lot of heat quickly.

As your motor is heating up, so too is your battery. A hot motor is also indicative of a setup that is likely pulling many more amps than the safety margin of the battery itself. You can actually calculate the safety margin of your battery using the following math:

mah x C rating / 1000 = maximum safe amp draw

So as an example, a common 11.1v 1450mah 20C LiPo (your typical buffer tube sized battery) has a maximum safe amperage draw of 29 amps. While this sounds like a comfortable amount, your average 18:1 / 30K motor build can easily pull in excess of that on the first round voltage spike, and many high speed motor / high speed gear setups will most certainly be pulling greater than 29 amps.

Thusly, exceeding the capabilities of the battery will ultimately result in damaging the individual cells through excess heat generation and other factors.

Disadvantages of Brushless Motors

The only disadvantage of brushless motors is the expense. Despite more manufacturers stepping into the brushless wading pool, the cost of these motors has not really declined yet - and in some cases has actually increased. On its own, the Warhead Black 30K runs $150 compared to the ASG Infinity series, which are $75. If you're working within a strict budget, then brushed will be a more cost-effective solution, and certainly far better than stock motor offerings, most of which rely on old-school ferrous magnets, which are comparatively much weaker than Neodymium.

To a certain extent, some brushed motor and gear combinations will actually have slightly better trigger response too. But this is a value measured in milliseconds, and as such, is analogous to putting titanium bolts on your rims... which is to say, as an end user you will not notice the difference.

TL:DR - or the quick-n'-dirty bullet list

In summary, brushless motors are the future. For players looking to improve battery life, trigger response, and have a setup that will run cool all day long under sustained use, you can't do any better than brushless.

• Greatly reduced amperage draw
• Improves your battery life
• Reduced heat generation
• Gobs of torque = excellent trigger response
• No brushes to wear out
• Ideal for users who like to 'spam' the trigger
• Ideal for AEG replica's that have limited battery space
• Also ideal for LMG's or builds where users are spitting out BB's in high volume
• Yes, they are expensive
• But... if you can swing it, it's worth the investment