KK 2.1 Flight Controller First Look

December 20, 2013 20:25 | By | 4 Comments

The new KK 2.1 arrived! This updated version sports an MPU6050 sensor, which should remove the rotation rate limitations of the KK 2.0 controller. A full review is coming, in the meantime check out the first look inside.


Not much has changed on first blush. The buttons and display are the same. There are several extra pin headers, the KK now supports plugging in a high-power LED right onto the board for easily-visible flight mode display. That LED is not included however, you still do get the Buzzer included in the package however.

What is new is the sensor: The old separate gyro and accelerometer chips have been replaced with a state-of-the-art MPU6050 which supports up to 2000 deg/s rotation rate sensing. For comparison, the DJI Naza M V2 supports up to 200 deg/s. Yes you can still do flips with a Naza, but they’re not designed for it. It’s clear which FC has the more capable sensor, though the KK 2.1 lacks a barometric pressure sensor, just like it’s parent the KK 2.0.


On the software side, there is currently no third party firmware available, aside from a v1.6 update straight from Hobbyking. However, there are some issues:

It seems that with stick scaling values of 50 or higher, the KK 2.1 board is prone to execute sudden, unexpected flips. This did not go away after updating the firmware to v1.6, and appears to be a yet-unresolved software bug. As an interim fix, we strongly suggest you set the stick scaling value to 45 or lower for now.

There are some features we loved in RC911’s third-party KK 2.0 “v1.6+” firmware, which are woefully absent in the official firmware here. Specifically: SBUS support, as well as the ability to have autolevel gain “fade out” the more you move the sticks away from the center, are both missing here. However, the KK 2.0 supports CPPM out of the box, so you can work with a SBUS-to-CPPM converter like the one produced by FrSky.


The backside hasn’t changed much, safe for the fact that Rolf Bakke’s name is no longer on it. Now, the manufacturer’s company name is emblazoned on it. According to Hobbyking however, they still pay royalties to Rolf.

How’s the flying? Remarkably unremarkable and rock solid. In terms of stability it gives the most expensive flight controllers out there a run for the money. Self-level performance is excellent but we still want to wait for the full review – as well as a fix for the stick scaling issue mentioned above – before making a final judgement call. Two things should be kept in mind though: This is a $30 flight controller and even in its current state it is easy to recommend, and the firmware is open source. In fact, the sourcecode is included inside the firmware update zip file, so it won’t take long for the community to pick it up.

Luckily for us all, RC911 has stated that he’s already working on a “1.6++” firmware, and he mentioned an ETA of roughly two weeks from now.  In the meantime we’ll fly the heck out of the new KK board and let you know what we find.


Tags: , , , , , ,

Category: News

About the Author ()

FPVCentral is a private, independent news and review site for all things related to First Person View RC model flight. Covering everything from hobby, commercial and military drones, RC models and electronics related to FPV flight, we are not sponsored by any manufacturer or affiliated with any company or project.

Comments (4)

Trackback URL | Comments RSS Feed

  1. Martin says:

    Hello All,

    I recently assembled a Flamewheel 450 and it flies well with one major exception. I cannot land the quad without breaking an arm or a prop. When I lower the throttle to descend it’s as if the 4th motor shuts off completely instead of in synch with the other three, thus causing a crash, EVERYTIME! I’ve calibrated the ESC’s. The props are balanced. The CW and CCW motors/props are operating in the correct orientation. All channels are operating properly. Has anyone else experienced this? If so, how did you fix it or can you point me in the right direction? I’ve read on various newsgroups that it could be my settings but all the information varies. I’ve also read that it could be a “lazy 4th motor”. I tried flashing the KK board with 4.7X but it didn’t work. I believe that firmware was for the KK 2.0 only. I’ve been flying multi-rotors LOS and FPV for over a year however I’ve only used the NAZA FC. This 450 houses a KK 2.1. The specs on my quad are below. Any assistance will be greatly appreciated as I’m starting to run out of spare parts. Thanks in advance.

    Platform: DJI 450
    FC: KK 2.1
    Firmware: Stevies 1.2S Beginner (All default settings)
    Motors: DJI 30A
    ESC: Turnigy Plush 30A
    Props: Stock DJI 10×4.5

    • fpvcentral says:

      That is really weird. If you did calibrate your ESCs properly, then I’d say switch two ESCs and check if it’s either the ESC that shuts off, or the KK board. If it’s the ESC then replace that, if it’s the KK board then I’d flash a different firmware, or get a new KK board.

      Oh also make sure that your ESCs are all set up the same way (i.e. same timing, etc)

      You might want to get a programming card for Plush ESCs to make that easier.

  2. joca says:

    Hello friend u solved the problem of the engine off, because I’m having the same problem in my kk2.1. I have searched answer when I found his request for help. I need help too. tks

    • fpvcentral says:

      See our reply above! Make sure the ESCs are calibrated and set up the same way (timing, etc.) and try swapping two ESCs to see if it’s an issue with the ESC or the KK board.

Leave a Reply