Shimano Direct Mount Lockring Tool

Shimano's direct-mount chainring system on the M9100, M8100, M7100 and M6100 series MTB cranks (XTR, XT, SLX and Deore) eliminated the separate chainring-bolt assembly by threading the chainring directly into a lockring that mounts on the crank's spider. The chainring locks against the lockring at a published install torque; removing the chainring means turning that lockring with the right tool. A generic socket won't fit; the lockring's outer engagement is a specific notch profile machined for the Shimano TL-FC41 service tool.

The 1723.SDL is the workshop replacement for the TL-FC41. CNC-machined aluminum, sized to the Shimano direct-mount lockring's specific notch profile, red-anodized so it doesn't disappear into the shop's drawer of black tools. Machined 32 mm wrench flats (SW 32) on the tool body take the 1725/CF crowfoot, whose 1/2" square drive accepts a torque wrench for the chainring lockring's published install torque; Shimano specifies a value, and the tool is designed to honor it.

Pairing with the 1725/CF Crowfoot

The 1723.SDL is designed to pair with the Crowfoot Open-End Wrench 1725/2CF and a 1/2" drive torque wrench for the published install torque. The crowfoot is the drive interface: its 32 mm open end engages the flats machined on the tool body, and its 1/2" square drive takes the torque wrench, so the lockring can be set to Shimano's specified fitting torque.

Compatibility

• Shimano XTR M9100 cranks (direct-mount lockring chainring)
• Shimano XT M8100 cranks
• Shimano SLX M7100 cranks
• Shimano Deore M6100 cranks
• Shimano-pattern direct-mount lockrings on aftermarket chainrings that follow the same engagement
• Replacement for Shimano TL-FC41

Specs

• Material: CNC-machined aluminum, red-anodized
• Drive: 32 mm wrench flats (SW 32), driven by the 1725/CF crowfoot with a 1/2" drive torque wrench
• Lockring fit: Shimano direct-mount lockring outer profile; 46 mm outer diameter (D), 30 mm tall (B), 58 g
• Includes: the tool itself

Built in Zreče

Unior has been forging hand tools in Zreče since 1919, and sponsors professional road and mountain-bike race teams. The 1723.SDL is the workshop's answer to a Shimano service tool that historically only lived in dealer service kits; a CNC-machined aluminum replacement with the right engagement profile, sized to take a torque wrench at the published install spec.

Pro tip from our mechanics

Direct-mount chainring lockrings sometimes seize against the crank spider after a season of riding, especially on bikes that see wet conditions. Before applying loosening torque, spray penetrating lubricant at the lockring-to-spider interface from the back side of the chainring and let it work for five minutes. The lockring backs off cleanly with the lubricant in place; without it, the lockring's outer notches can round under loosening torque before the lockring breaks free, which converts the chainring swap into a more involved removal.

For the crank removal procedure with chainring-access calls: How to remove a crankset →.

FAQ

Which Shimano cranks does the 1723.SDL fit? Unior lists compatibility with all Shimano direct-mount style cranks in the M9100, M8100, M7100, and M6100 series, which are the XTR, XT, SLX, and Deore groups. The tool engages the outer notch profile of the chainring lockring on those cranks.

Is the 1723.SDL the same as Shimano's TL-FC41? Unior's own wording is Replacement for Shimano TL-FC41. It is CNC-machined aluminum, red anodized, with the same lockring engagement as the OEM tool, so it installs and removes direct-mount chainrings the way the TL-FC41 does.

How do I torque the chainring lockring with this tool? Seat the 1723.SDL on the lockring and drive its 32 mm flats with the 1725/CF crowfoot on a 1/2 inch drive torque wrench. Unior specifies that pairing so the lockring can be fitted as Shimano specifies; use Shimano's published figure for your crank, since Unior does not reprint the number.

Does it fit Shimano STEPS or other e-bike motor lockrings? No. The 1723.SDL is machined for the direct-mount chainring lockring on Shimano cranks. The lockring on STEPS drive units takes Unior's 1724.SSL, and Fazua Ride 60 motors take the 1724.FR60, so pick the tool for the lockring you are actually turning.