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Direct Mount Chainrings for SRAM 8-Bolt Gravel / Road Cranks
SDM8-40
Pairs well with
Wolf Tooth Direct Mount Chainrings for SRAM 8-bolt Cranks replace your existing spider and chainring with one clean looking, lightweight, and stiff piece of machined billet. They feature our patented Drop-Stop® design for the best wear life, chain retention, and mud clearance. Drop-Stop B is optimized for SRAM Eagle and Flattop chains.
Compatibility
- Aero chainrings available in 46-52T. Sizes 34-44T are non-aero.
- These direct mount chainrings will replace your existing chainring and spider or replace the direct mount chainring for SRAM AXS cranksets and other cranks that use the 8-bolt mounting standard.
- SRAM Direct Mount DUB road cranksets use the 8-bolt mounting standard. Any of those cranksets with a removable spider also use the 8-bolt mount.
![](https://cdn.shopify.com/s/files/1/0230/9291/files/SDM_3-8bolt_480x480.jpg?v=1584982156)
- Compatible with SRAM 12-speed and 13-speed groupsets including SRAM Red XPLR AXS.
- Wolf Tooth’s patented Drop-Stop® wide/narrow tooth profile for the ultimate chain retention and mud-shedding ability.
- For 38-52T chainringsChainline is 45mm on standard spindle cranks and 47.5mm on wide spindle cranks. For 34t and 36t chainrings Chainline is 47mm on standard spindle cranks and 49mm on wide spindle cranks for wider tire clearance in bikepacking applications.
Recommendations
- Recommend the use of a clutch-style rear derailleur for the best chain security
- For Installation, use the included custom T20 bolts. Torque to 4Nm with a T20 bit.
Tech Specs
Material: 7075-T6 aluminum
Made in the USA
Wolf Tooth is committed to provide the most precision components possible and has three different tooth profiles for optimal performance based on your chain type.
Tooth Profile | |||
---|---|---|---|
Tooth Profile |
Drop-Stop® B |
Drop-Stop® A |
Drop-Stop® ST |
Chain Compatibility | |||
Chain Compatibility |
All 9s, 10s, and 11s Chains 12s Chains:
Not compatible with 12s Shimano HG+, 12s KMC, or 13s Campagnolo chains |
All 9s, 10s, and 11s Chains 12s Chains:
You can use Drop-Stop B when Drop-Stop A is not available* Not compatible with 12s SRAM Transmission (T-Type) and Road Flattop, 12s Shimano HG+, 12s KMC, 12s Campagnolo, or 13s Campagnolo chains |
12s Chains:
Not compatible with all other chains |
Details | |||
Details |
![]() Tooth shape is nearly identical to Drop-Stop A, but has narrower teeth. Valley between teeth is deeper to accommodate larger rollers on Flattop chain. Outside faces of narrow and wide teeth touch chain to guide alignment. Drop-Stop B Chainrings |
![]() The original Drop-Stop tooth profile. The wide teeth are wider than Drop-Stop B. Outside faces of narrow and wide teeth guide chain alignment. Drop-Stop A Chainrings |
![]() Narrower teeth than Drop-Stop A. Wide teeth use Symmetric Trapezoidal (ST) profile to match extended inner edge on chain to create alignment (outside faces of wide teeth do not touch). Interaction of narrow teeth and chain are similar to Drop-Stop A and B. Drop-Stop ST Chainrings |
*We are in the process of migrating most Drop-Stop A to Drop-Stop B to make them compatible with SRAM Road and Transmission (T-type) Flattop chains.
WARNING
Handling this product will expose you to chemicals, including lead, known to the State of California to cause cancer and birth defects or other reproductive harm. Wash hands after handling. For further information go to www.P65Warnings.ca.gov.