Service Advisory 2021-01


April 02, 2021


February 09, 2021


We recommend all Mamba XLX2 ESCs be updated. The ability to update via your Castle B-Link Adapter with Android or Apple iOS will be available by end of day.

Please note that the firmware update for the Mamba Monster X 8S that will allow the use of D-wind motors as well as motors greater than 2000kv, is forthcoming.

January 07, 2021

It has come to our attention that a limited number of Mamba XLX2 ESCs have experienced a failure upon plug in or while running. Most users report no problems with the XLX2 but after considerable investigation and root cause analysis, we would like to share the following information.


Advisory applies to: MAMBA XLX2, 8S, 33.6V ESC, 20A PEAK BEC (Item # 010-0167-00) and MAMBA MONSTER X 8S, 33.6V ESC, 8A PEAK BEC (Item # 010-0165-00)

At this time, Castle is advising to immediately discontinue use of Delta wound motors and any motors that are 2000Kv or higher.

Three phase motors come in two common wiring patterns, Delta (D-wind) and Wye (Y-wind).  Each pattern has its own power characteristics and Castle motors have a Y-wind design. Our current data suggests that D-wind motors, especially larger motors (40mm x 80mm or longer and 56mm diameter or larger) and any motors that are 2000Kv or higher are not currently suitable for operation with the Mamba XLX2 or Mamba Monster X8S. Running these motors can result in abnormal operation and may lead to premature ESC and/or motor failure.

If you are unsure whether the motor you are running or intending to run is a D-wind, please contact the motor manufacturer.

Castle is working on a firmware update that will allow the use of D-wind motors and motors greater than 2000kv. Once released, all XLX2 and Monster X 8s ESCs can be updated via the Castle Link USB programmer or B-LINK Bluetooth™ adapter to the new firmware. The estimated availability for this firmware is the end of January 2021.



Advisory applies to: MAMBA XLX2, 8S, 33.6V ESC, 20A PEAK BEC (Item # 010-0167-00)

A small number of XLX2 units from the first production build could experience an internal hardware failure. Busbars that are housed within the Mamba XLX2 circuitry may, in limited circumstances, be misaligned and cause a malfunction to occur during the very first use of the ESC, whereby the ESC may beep and then stop responding.

Anyone experiencing this type of failure is encouraged to contact Castle for a warranty service. The manufacturing lot codes of this build are C27255, C27711, and C27964. This information is contained on the label adhered to the wires on the ESC and on the outside of the product box. Note that this issue has been addressed in subsequent manufacturing runs.

If you would like to have your ESC inspected and tested for this issue, please submit an SA2021-1 RETURN FORM  and ship the ESC to Castle Creations, Attn: Service Advisory, 540 N. Rogers Rd. Olathe, KS 66062. 

If it is determined that the unit exhibits this problem, it will be replaced with a new unit.



Advisory applies to: MAMBA XLX2, 8S, 33.6V ESC, 20A PEAK BEC (Item # 010-0167-00)


The XLX2 is a high-performance controller with specific system requirements designed to protect the integrity of your ESC and ensure maximum performance. Please refer to the Mamba XLX2 Product Use Statements for information regarding calibration, input voltage, minimum battery requirements, wiring, soldering, connectors and more. It is critical that all relevant components in your system be able to support the incredible power handling and performance of the XLX2.

"Sensored Only" Operation

“Sensored Only” motor operation is strongly discouraged. This mode may cause motor timing variability and lower motor efficiency with higher temperatures, causing unnecessary strain on the ESC, motor and batteries.  There is no standard RC application in which sensored only mode is recommended.

The default mode, SmartSense™ enables the ESC to use the sensors to start the motor smoothly, then transitions to sensorless mode while running for more efficient motor timing. This is the ideal setting to run your motor at maximum efficiency.


The input voltage max for a Mamba XLX2 is 33.6V. As such, 8S HV LiPo packs charged to above 33.6V (4.2V/cell) cannot be used with the Mamba XLX2.

Low voltage cutoff

If you must disable low voltage cutoff to prevent the ESC from shutting down, then your batteries are insufficient for your application. 3.2V per cell is the lowest a LiPo battery should ever be discharged under load. Utilize XLX2 data logging capability of the XLX2 to verify your batteries are not dropping below this level. Exceeding the capabilities of your LiPo batteries can lead to catastrophic failure of the battery and/or ESC. Do not disable the low voltage cutoff with LiPo batteries!



The Mamba XLX2 requires the use of connectors designed for 150+ amps of continuous current. Do not use Deans™, Traxxas™, EC3/XT60, EC5/IC5, XT90/XT90S connectors in your Mamba XLX2 setup! 6.5mm or larger connectors are recommended (i.e. Castle 6.5mm polarized connectors or QS8/OS10 anti- spark).


As always, the Castle Tech Support team will gladly review your setup and is available answer any questions. We are hobbyists too and we want you to have the best experience possible!