Off-road motorcycle drive chain tensioner - has arm with sprung slide to maintain constant tension at all positions of suspension arm

摘要

The motorcycle chain tensioner maintains the chain under constant tension when the rear suspension deflects. The tensioner consists of a link (14) pivoting about an axis (15) fixed to the swinging arm of the motorcycle. A pin (20) fixed to a sliding shaft (21) engages in the slotted lobe (19) of the link (14). The shaft (21) slides in a guide (22) and is attached to the chassis by a spring (24). As the suspension oscillates about the pivoting axis (7) of the rear forks, the drive chain oscillates about the gear box sprocket (12). The slackening of the chain is compensated for the pivoting of the link under the action of the spring and slide.