Shimano Tourney TX RD-TX800 7/8-speed rear derailleur

Shimano Index System (SIS)

The Shimano Index System consists of a shift lever with a detent function and a friction-minimized SIS shift cable that controls the smooth-running rear derailleur.

Hyperglide (HG)

The specially shaped Hyperglide sprockets feature special tooth profiles as well as specifically positioned climbing aids that optimize chain guidance during shifting. This enables fast, precise index shifting. The HG cassette, developed for 10-speed mountain bike shifting, has undergone extensive optimisation measures to achieve supperefficient shifting functions.

Double Servo

Shimano's Pantograph double servo mechanism allows the rear derailleur to move in an optimal path. The guide pulley tracks the sprockets as they move forward and backward at very close intervals, optimizing each shifting operation. The perfect tracking contributes to the extremely precise SIS shifting operations. The guide roller of the rear derailleur is equally optimal to the sprocket in all gears.

Specifications