![Drop-Stop B / 42T Oval Direct Mount Chainrings for SRAM Gravel / Road Cranks](http://www.wolftoothcomponents.com/cdn/shop/products/WT_OVAL-SDM42-FT_01.jpg?v=1702077124&width=2000)
![Oval Direct Mount Chainrings for SRAM Gravel / Road Cranks](http://www.wolftoothcomponents.com/cdn/shop/files/WT_OVAL-SDM42-FT_02.jpg?v=1702077285&width=2000)
Oval Direct Mount Chainrings for SRAM Gravel / Road Cranks
OVAL-SDM38-FT
Pairs well with
![Logo for PowerTrac Elliptical, Wolf Tooth's proprietary design for bike chainrings.](http://www.wolftoothcomponents.com/cdn/shop/files/POWERTracLogoLgRed.jpg?v=1613557135&width=1500)
More power, better traction, less shifting. Wolf Tooth oval chainrings use our proprietary PowerTrac design that has all the benefits of oval, but without the funky, uneven pedal stroke. Ride one once and you’ll wonder why you waited so long to try oval.
Think of an oval chainring as two chainrings in one. A major benefit of oval is how the shape of the chainring alters your gearing in two important phases of your pedal stroke by harnessing your body’s natural biomechanics. Here’s how it works. The area of the chainring with the larger diameter engages with the chain at the optimal point on the downstroke, which is what’s known as the Power Zone. If you were to look at a clock, the Power Zone would be between 1-5 and 7-11. Conversely, the Recovery Zone – back to the clock face, between 11-1 and 5-7 – is the weakest part of the pedal stroke, when the oval maximizes your efficiency. A 34T oval chainring behaves like a 36T chainring when you want power, while behaving like a 32T chainring when you’re climbing.
We’ve also engineered our oval chainrings to provide smoother, more efficient pedal rotation. This equates to better traction because of steadier torque on the rear wheel. With a Wolf Tooth oval chainring, you can harness more of your strength in the Power Zone, while having easier pedaling in the Recovery Zone.
The direct mount chainrings for SRAM cranksets with the 3 bolt mounting interface. They replace your existing spider and chainring with one clean looking, lightweight, and stiff piece of machined billet. They are available in the Drop-Stop B tooth profile, which is optimized for SRAM Flattop chain. It is also compatible with all other 9, 10, 11, and 12 speed chains except Shimano 12spd chain.
Compatibility
- These direct mount chainrings will replace your existing chainring and spider or replace the direct mount ring on SRAM cranksets including the DUB cranks. The ring is attached via 3 bolts on the back side of the spider near the spindle. Note that these chainrings are NOT compatible with SRAM 8-bolt direct mount cranksets.
- Wolf Tooth’s patented Drop-Stop® wide/narrow tooth profile for the ultimate chain retention and mud shedding ability
- There is one offset:
- Standard Road/CX/Gravel: 6mm offset for cyclocross and road crank applications with 47mm chainline
- Praxis Works Road/CX cranks use the 6mm offset.
![](https://cdn.shopify.com/s/files/1/0230/9291/files/SRAMDMoffset_chainline_chart_1_1024x1024.jpg?v=1689185066)
![](https://cdn.shopify.com/s/files/1/0230/9291/files/offset_chainline_1024x1024.jpg?v=1689185101)
- If using a 9-speed drivetrain use a 10-speed chain (shifts and works well on a 9-speed drivetrain and fits the ring tighter for better chain retention).
Recommendations
- Recommend the use of a clutch style rear derailleur for the best chain security.
- An L-wrench works best since the crank spindle may contact a socket adapter and prevent it from engaging properly.
- Use the same 3 bolts to attach the Wolf Tooth ring or we carry replacement bolts
Related Products
- For a longer lasting and more durable option check out the CAMO System that offers stainless steel chainrings.
- We recommend using a T25 L-Wrench or similar for removal and installation of the bolts.
- The stock bolts are easily damaged when removing them to install a direct mount chainring. We have replacement bolts if you need them.
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.