SPECIAL NOTE:- I have Just Completed A Manual For The BK Brake Assembly.

Includes Installation & alignment information.

Consists of 4 colour pages:- includes 1 page of text, 2 pages with 31 pics + 1 of logos.

Comes laminated & is available from the MANUALS PAGE. 


Below are pics & list of the parts in the Emotator BK brake assembly.




The BK brake assembly is made up of 5 parts & Emotator part numbers are different for each model:-

I have simplified the Emotator Part Number to a common Part Number, see below.

(1) BK Butterfly, comes in a few different version depending on the motor shaft size.

(2) BK Spring (BK-26 ), Is the same spring for all Brake assemblies.

(3) BK Housing (BK-27 brake drum), Comes in two versions Aluminium or Plastic.

(4) BK Pinion (Pinion with BK arms), Comes in different versions depending on motor shaft size.

(5) BK Retainers, Also known as Push Nut, comes in different sizes.

Emotator uses the BK brake assembly in most of it's rotators (excluding 102, 103, 105, 1000, 1100, 1102 & 1103).

The BK Spring in the most important part of the assembly, without it the rotator will have non or very low brake torque.

The brake torque of a rotator is calculated down the reduction gearing onto the motor pinion/BK spring, without the BK spring the motor spins freely, hence NO brakes.

When the BK spring fails it is caused by only a few factors:-

(1) Lack of servicing, old gooey sticky grease gumming up the BK & gearing.

(2) BK butterfly coming loose on motor shaft & dropping down, loosing contact with the top return of the BK Spring.


NOTE1 : For the BK Brake Assembly to work properly the BK pinion MUST spin freely on the motor shaft, if not the brake will not work.

NOTE2 : The BK Housing must be aligned properly, as not to be hit by the spinning BK Pinion.

NOTE3 : The BK Butterfly must be tight on the motor shaft & be aligned so it grabs both ends of the BK Spring.


Written by Peter Hasting of DUORO SERVICES Australia

Updated 11/05/2019