The KHEbikes Bush Bottom Bracket offers a lightweight and durable alternative to the classical sealed bearing BB through superior plastic bearing technology.
The KHE AFFIX BB come with a set of needle side bearing on the side which help overcoming the side friction when the crank is tight and greatly help the adjustement of the BB.
The KHEbikes Bush Bottom Bracket is made of a proprietary composite material that combines high performance polymers with precise additions of fibers reinforcements and solid lubricants. Because of its intrinsic advantages, plastic bush bearings have replaced metal bearings in thousands of applications from all industries, ranging from medical devices to food processing, marine equipment, pumps and valves or automotive applications.
The bush bearing is not a rolling bearing, it is a friction bearing (it is not rolling, it is sliding). This means there is more friction involved, the crank spin less than with a regular rolling bearing. BUT the coefficient of friction changes with the load.
As shown on the graphic in the slideshow, the coefficient of friction highly decreases when the bush start to be loaded. The coefficient of friction is changing to a value that to a large extent is constant.
This means that when you start pedalling, the crank is a bit harder to turn, but when you ride, you do not feel any resistance anymore. In addition, when you are not pedalling, the pedals will not move by themselves as easy as with a rolling bearing. This means that on no footer or tailwhip variations the pedals will stay in place.