There are actually two types of links alternating in the bush roller chain. The 1st type is internal links, having two inner plates held collectively by two sleeves or bushings upon which rotate two rollers. Inner links alternate with the second type, the external links, consisting of two outer plates held with each other by pins moving through the bushings of the internal links. The “bushingless” roller chain is similar in procedure though not in construction; instead of separate bushings or sleeves keeping the inner plates with each other, the plate has a tube stamped involved with it Leaf Chain protruding from the hole which serves the same purpose. This has the advantage of removing one part of assembly of the chain.

The roller chain design reduces friction in comparison to simpler designs, resulting in higher efficiency and less wear. The initial power transmission chain varieties lacked rollers and bushings, with both the inner and external plates held by pins which directly contacted the sprocket tooth; however this configuration exhibited incredibly rapid wear of both the sprocket the teeth, and the plates where they pivoted on the pins. This problem was partially solved by the advancement of bushed chains, with the pins holding the outer plates moving through bushings or sleeves linking the inner plates. This distributed the put on over a greater area; however the the teeth of the sprockets still wore quicker than is desirable, from the sliding friction against the bushings. The addition of rollers encircling the bushing sleeves of the chain and offered rolling contact with the teeth of the sprockets leading to excellent resistance to wear of both sprockets and chain as well. There is even very low friction, provided that the chain is certainly sufficiently lubricated. Constant, clean, lubrication of roller chains is certainly of primary importance for efficient operation as well as correct tensioning.