The derailleur of a mountain bike has the task of guiding the chain and to position it accurately on the gears of different sizes, which provide for the different transmissions. iglidur® G polymer plain bearings from igus® reliably do their job in the guide roller of the SRAM control unit provided in all articulated points. Thus they also satisfy world class mountain bikers.
The guide roller of a mountain bike derailleur moves by a parallelogram mechanism. This must take an accurate position in the three-dimensional space as the chain pinions stay very close together, and variations can lead to noises or to chain jumps. The control unit is thereby subject to several environmental effects such as water, mud, sand and oil. Cleaning with the steam blaster and mechanical stressing, for instance through jumps, also add to the adverse influences. Two iglidur® G plastic plain bearings from igus® are seated in each of the four points of articulation. Thereby an accuracy and long service life can be achieved, and also fulfill the demands of professional mountain bikers battling for medals.
The potential weight saving constitute an important criterion and speaks in favor of the application of plastic bearings in the high-tech mountain bikes. In contrast to the previous direct bearing in plastic, aluminium or brass bushings, which featured high friction and wear and low accuracy, the iglidur® G bearings operate moreover extremely precisely and prove to be almost indestructible. The economy is thereby determined primarily by its long service life, which is predictable online. Moreover the MTB maintenance of the machine parts are dispensed with, which proved to be very difficult in the application locations.