Shimano Deore XT RD-M781 Bracket Axle Unit (Y5Y098010)
What it is
This is the main mounting pivot assembly that connects your rear derailleur to the derailleur hanger on the frame. It includes the axle/bolt system that allows the derailleur body to rotate and move smoothly when shifting.
It is not a “functional shifting part” like a pulley or cage — instead, it’s a structural joint and attachment interface.
What it does
- Attaches derailleur to frame hanger
- Acts as the pivot point for derailleur movement
- Maintains correct alignment under chain tension
- Includes the lower mounting bolt/axle assembly
Compatibility
This exact Shimano OEM part is used on:
- Shimano Deore XT RD-M781
- Shimano Deore XT RD-M786
- RD-M781-D / RD-M786-D versions
It is also:
-
“A match” for those models → same material, size, finish, and design
-
“B match” usable with:
- SLX RD-M675
- SLX RD-M670
(but with minor differences in finish or materials)
Shimano part number
In simple terms
If your derailleur still works but:
- the mounting bolt is broken
- the pivot is worn or cracked
- the derailleur is loose on the hanger
