That's a bold statement ... Worlds Best. But it's even larger than that. Not just Worlds Best, but best for most all applications less than 30 Amps (limit of the tests). That means:

- duration ships that only pull 2 to 8 amps per rotor

- most all 6S and smaller ships (exception of nano-ships)

- any-size FPV racer

- any other ship in between

Why almost any size? Shouldn't a small FPV racer use a smaller and lighter ESC for response? Yes, if it does better on a net-lift response test. In other words, when you penalize the ESC for it's weight, is it still better and faster? What i continue to see is ESC manufacturers downsizing critical components of the ESC at a net loss. They weight savings is lost because of greater thrust loss and response. In other words, this heavier ESC will out accelerate, in the real world, a smaller and lighter ESC.

Why post this? To move technology forward, we need to report to industry what works and what doesn't. For some reason (i don't know why), this ESC works better than all others tested:

- for generating maximum thrust from the motor***

- for net-lift efficiency or the grams of weight it can lift (after it lifts the rotor) per watt

- for response (how fast it can generate targeted lift)

These tests were conducted on multiple days on multiple rotors of highly variant size, always being immediately compared back to another DYS 40A multicopter test to ensure that the baseline wasn't changing.

The ESC that dominated is a DYS 40A OPTO Multicopter using SimonK. The photo is included because there are two others that carry a similar or same name.

- Not the white cover DYS BLHeli 40A

- Not the one that is says "Programmable" versus "Multicopter" in the blue/purple band across the front

Have i tested all ESCs? No, but if you are convinced you know of one that would work better, let me know. I've tested most all of the following and one or more of their variants:


- Multistar

- Turnigy

- T-Motor

- Afro

- Motortron

- Quattro

- 3DR

- Spider



- Aris


- AutoQuad

- Exceed

- HobbyWing

- Lumenier

To do a test like this, a highly repeatable and finite test stand is needed. It took a while to develop one but what works is one that:

- measures (at a minimum) volts, amps, thrust, motor temp (shoots IR up the aft end of the motor)

- eliminates harmonics between the rotor and load sensor (this proved difficult but achievable)

- is calibrated and proves repeatable within 1.5%

- controlled by a system that can precisely repeat a rotor test (uses a Audurino Mega)

- directly feeds the data into Excel for analysis (uses DATAQ)

- uses a test script that produces repeatable results

- uses a test procedure that minimizes repeatability error (used average of multiple tests)

How much better is this ESC?  On average:

- 4.4% higher net lift (after it lifts itself)

- 2.3% more net-lift efficient (usually the larger the better)

- from more than twice the response or the same response as other ESCs (usually the larger the better)

                                                       So how to make it better?

Step 1: Strip it naked. See photo below.

           ... remove the cover

           ... remove the heat plate (better to locate the ESC under prop wash to run cooler, see below)

Step 2: Right-Size the bullet connectors or wires (see above where heavy wires are replaced by 2mm bullets)

           ... remove the large bullet connectors or wires

           ... replace them with ones that are the most net-lift efficient (where heat loss = weight loss)

Step 3: Seal the ESC. Seal it with Electrical Sealant to protect from moisture and conductive dust

           ... tape or plug connectors and wires

           ... repeatedly spray each side from different angles

           ... a mistake i made was not sealing the bullet connectors and solder

               - don't tape them off like i did

               - insert a male connector into the end of bullets so sealant doesn't get inside them

Step 4: Locate ESCs under Prop Wash. See photos below. The turbulence generated by the prop does not adversely affect lift when the ESC is placed on edge to the prop wash.

           ... Use something non-conductive like hot glue to bond the ESCs to the motor mast or spar

           ... Face the FETS (the little square warehouses or Fire Emitting Transistors) to open air

           ... Protect the ESCs from below from ground contact (not needed here because of clearance)

back-side with hot glue

front-side with FETs completely exposed to open prop wash

Step 5: Tie up wiring. Use dental floss to secure wiring away from the prop.

***Note: The T-motor Air 40 in high-timing mode (an option) generated higher thrust, but at the sacrifice of efficiency and motor temp. Also, the T-Motor Air 40 was 2nd best and close in performance. If you are using an Air40, it probably isn't worth switching.

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Ouch!!! that cactus :O  thank's :D

Forrest -

One simple question:

What is the max E-RPM on your ESCs?

What we call "performance" is power to weight in the range of 8:1-10:1. An average build is pulling around 1KG per motor on 5" props and in excess of 1KG thrust per motor on 6" props with a 500-600 gram quad. 

On top of that, we expect it to handle like a hummingbird on crack, so we need not only fast acceleration, we need massive braking performance. Do your ESCs even SUPPORT active braking?

Simple straight-line performance is totally 2008. ;)

Sorry... your ESCs just can't cut it. What we consider to be a total "Team Nana" build would leave any quad built with those ESCs in the dust in the first turn; they just can't turn the RPMs we NEED for the way we fly. Modern racing ESCs are working so fast, talented folks like my friend RS2K are writing entirely new protocols for them to talk with the FC because PWM is just plain too flupping slow.

I suggest you scope out Quad McFly's performance database to see what I'm talking about, and to see the kind of ESCs and motors we actually RACE WITH.

Once you see the setups actual racers use, then you'll understand; you're comparing a Cummins TurboDiesel to a V12 Ferrari. If we were RACING dumptrucks it might be a good idea, but we're racing Formula 1. ;)

Right now, this is the fastest growing segment of both QuadCopters AND Model Aviation; we just had the World Drone Prix in Dubai, where a scary-talented 15-year-old kid won a cool 1/4 mil. Quad Racing is right now on the cusp of going completely mainstream; it's the next X-Games. Seriously.


This is where I usually put some pithy remark.

@Paul Great to see there's some innovation going on in the ESCs, even if it's very specialised.  The fact we're effectively doing D2A A2D D2A conversions from the FC to ESC to Motor in the 21st century is crazy. 

I think Forest's title for this blog is pretty silly, it's clear that his interests lie within a particular defined set of parameters that don't cover every eventuality.  Yours with fpv racing, I put my ESCs in CF tubes so that pretty much rules out every ESC Forest has tested, others lifting much larger UAVs won't find anything here of interest etc etc.  However, what he's doing is interesting as base research and he is looking at the most common set of parameters - the general small/midrange UAV - so it probably applies to the vast majority of the bell curve, so to speak.  The type of ESCs you're talking about have little interest to 99% of the UAV community outside of fpv racing.  Which is fun, and makes headlines with pretty leds, star wars getups and real-life computer gaming, but is probably a drop in the ocean of the overall UAV market. 

@Paul FPV racing is life and should be taken as seriously as real racing! Can I get an amen? What a bunch a noobs...

Yes. I'm familiar with that site. Excellent work.

- That site list the best rated ESC is the HobbyWing X-Rotor (i tested the 40A version)

- His site did not test the 40A DYS Multicopter, which

  ... beats the above in max net-thrust (defines the top end of acceleration)

  ... beats the above in nnet-lift efficiency (g/w after it first lifts it's sorry ass)

  ... they match response

- So if that is the ESC you are using, don't feel bad. You are almost using the best.

Too many manufacturers and pilots rely on the wrong criteria.

For example, RPM. One doesn't win races by a motor that can accelerate and decelerate without a prop. The criteria that matter is when you put the iron to the metal and test ESCs on 250 FPV Racer motors. Then the only criteria that matters (having blue blood doesn't count): 

1) Thrust acceleration (+ and -) is the only criteria that matters in terms of response

2) Maximum Net-Thrust (thrust generated after lifting itself) determines how far acceleration can reach.

So those that want to look at meaningless criteria, "Red is the only color I consider", might be happy, but will lose races.

Confession: I'm too sucky of a pilot to race FPV, so hats of to those that do. But my brother an i sponsor an FPV winner. So yes, we have a lot of experience in building ships that haul ass and can turn on a dime.

Offer and Challenge to Other FPV Champions: If there is a proven champion that is open to improving his FPV racer ship. I'll be glad to help. Every change is carefully done with through testing first. But the final test is in your hands maneuvering and racing the ship. I can guarantee a 20%+ improvement in acceleration of any champion's ship. The only question will then become, "Are you good enough to fly it to it's full potential?"

I thougth that I was crazy building a racer cuad if I'm too sucky too to race FPV, only to entusiasm young boys, and take pictures, but I'm not alone in this world :D :D

The ESCs were tested on a full range of rotors using eleven different propulsion setups:

Application              Motor                                    Propeller                        Battery

FPV 250 Racer        T-Motor 2206-13    2000KV       GemFan 6045 ABS          3S & 4S

FPV 500 Camera     T-Motor MN3508-29 380KV       GWS 12x6.0 Plastic         3S to 6S

amera Ship             T-Motor MN3508-29 380KV       T-Motor 17x5.8 Carbon     3S to 6S

Heavy Lift               T-Motor U10                             T-Motor 30x10.5 Carbon    6S

The ESCs consistently delivered the same relative performance in all the tests (within their amperage limits). Strange but true. When tested on a net-lift basis (size hurts), what was best for the Heavy Lift category was also best for the 250 Racer category (which by the wa6

Are the words "World's Best" too much. I'm waiting for someone that can suggest an ESC that beats the DYS 40A Multicopter as applied to any one of those four categories ... because i want:

- to use it.

- to let the manufacturer know how good it is

- to get others to buy it and use it and reward the manufacturer

- to let other manufacturers know what is their next target

Until someone finds or builds one (i'm hoping that's soon) that is better in even one, let alone all for of the above categories, then why not call it what it is? 

ESC Manufacturers: When building a team, a good coach focuses first on fundamentals. The DYS 40 Multicopter has done that. My suggestion is, figure out what the DYS does. If possible, improve on those fundamentals, then build on that foundation.

Since when isn't FPV racing real racing? And it's the fastest growing segment of the multicopter market.

Hallelujah!  I heard it's on track to be an Olympic event for 2018.  X-games is weaksauce.

If you are referring to the above mentioned person doing testing, he does test with multiple props and motors not motors without props, The dys40 is a good choice for low kv motors. The F330 base esc's are a thing of the past for fpv racers. The f39x's are the way to go. The f330's can not keep up with Betaflight's full potential. Most serious racers use Betaflight and are going for the maximum potential and these units will not handle it. Now for normal flying these are very good choice.

The above reference definitely does not apply to the above testing, which is done well and shows the same as i've found (except that they haven't as yet tested the above ESC).

Words, in my book, mean nothing unless they translate to actual measurable performance. Marketing tries to do the opposite ... make words mean everything. Betaflight, regenerative braking, 32 bit ... are all great only if they can show measurable response difference with the props on in terms of actual thrust response. 

So stick to the test data. Show me an ESC that outperforms the "old" tech in response ... please. I'm still waiting ...


Since you still didn't answer my questions, I looked up your pet ESC on the DYS site.

As I suspected, it does not support either 1-Shot125 OR active braking of any sort.

These are MINIMUM REQUIREMENTS nowadays for a "Race-Ready" ESC.

THAT is why Ryan never bothered to test them. They're stone-age bunk.

They are AIRPLANE ESCs with 3 generations out of date SimonK firmware from 5 years ago. They are made for the "AP Airship" market; quads that haul cinematographic camera gear  and NEVER leave a hover.

They are NOT "Race ESCs" by ANY definition of the word. PERIOD.

Today's Race ESCs handle 60A surge current on a 20A rated ESC, because that is what today's racers demand. The latest generation have 32-bit Silabs F390 processors, because 8-bit processors can't keep up. 

FPV Quads are another thing altogether. They fly high speed, mostly FFF in 40-60° forward tilt, and they fly acro, flipping and tumbling and piro-ing like a 3D Heli.

For that you need to not ONLY be able to accelerate rotating mass quickly, you ALSO need to be able to STOP the props just as quickly. 

These MB30040s are stone-age crap that simply doesn't cut it anymore.

Now don't get me wrong; I LOVE me some DYS. I have their motors on a dozen quads, and their BL20A ESCs on several and their XM20As on another.

You want to see some SERIOUS performance from DYS targeting REAL RACING applications? Look at the XM20A and XM30A.

Yeah, you read that right. 50MHz clock. 3000hz refresh rate. 9.2 freaking grams.

The MB30040 are ancient boat anchors don't even hit on their radar screen, they're so long out of date. 500Hz? PuhLEEZE. 39 FREAKING GRAMS?!? :rolleyes:

That's 1 ESC that weighs more than 4 real race ESCs. That would mean adding 90 grams of unsprung weight to a 500 gram build. The math is pretty easy. NO FREAKING WAY. ;)

And even those DYS are what we consider to be third or 4th string; the X-Rotor 40As are STILL tougher and faster. As are the KISS 18A and even the Zeus 20A/FVT LB20s.

So REALLY. These are NOT a "Muticopter" ESC by today's standards. They're a Heli ESC at best, REALLY an Airplane ESC with slightly modernized FW.

The guys who are buying the ESCs I directed you to are the guys who fly at the Drone Nationals and the World Drone Prix in Dubai. I PROMISE you, they aren't flying ANYTHING like these antiques. I know several of them personally.



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