5. Connect backrest tube (5) and chest-extension rotating frame (7) through the rotating bearing
(25), tighten with Hexangular floriated bolt(M8*10mm) (30). Secure bearing bases (38), washers
(26) and bolts (M10x25mm)(6).
Attach chest-extension handlebars (8R&L) to the chest-extension rotating frame (7), which was
already attached to backrest tube (5) in step 4, with washers (26) and bolt (M10x30mm)(7). Slide
crossed bearing covers (29) to the chest-extension handlebars (8R&L), tighten with nut canopy (58).
Connect pulling bar (27R&L) and crossed bearing cover (29) through limiting bushing (31), bolt
(M12x120mm)(19), powder metallurgy bushing (74) ,flat washer (33),dish washer(32) and locknut
(24).
Attach chest-extension handlebars(8L&R) to the fixing tube(50) with bolt(M10x75)(13) and
locknut(M10)(23).