The installation adjustment and pre tightening of LR series guide rail rollers are carried out through their eccentric inner rings. The LR series roller is a concentric design structure, and the eccentric structure design roller has two blind holes on one side of the inner ring for adjusting the clearance. If the roller is positioned at zero position, the meshing clearance between the rack and gear is 0.05mm. Excessive pre tightening may shorten the service life of the entire system. Insufficient pre tightening may cause the rollers to not operate or result in unexpected wear and tear of the system due to poor engagement during system operation.