- 100 day return period
- Online since 1998
- Trusted Shop 4.86 / 5.00
Application: Cross Country, All Mountain, Trail
Mount: SRAM Direct Mount
Teeth: 28 t, 30 t, 32 t, 34 t
Gearing: 1x9-speed, 1x10-speed, ,1x11-speed, 1x12-speed
Type: oval 10 %
Offset: 3 mm (Boost)
Chainline: 52 mm
Material: aluminium (7075-T6)
- all 10-speed, 11-speed, 12-speed chain except Shimano 12-speed
- for 9-speed drivetrains, a 10-speed chain is recommended
- Wolf Tooth PowerTrac Elliptical design and wide/narrow tooth profile
- smoother, more efficient pedal rotation, better traction, easier pedaling in the recovery zone
- Timing: 112° after TDC (Top Dead Center)
- Boost chainline (3 mm offset), 148 mm rear hub spacing
- design and manufactured in Minneapolis, MN (USA)
Notes: These direct mount chainrings will replace your existing chainring and spider, which is attached via 3 bolts on the back side of the spider near the spindle. You will use these same 3 bolts to attach the Wolf Tooth SDM® chainring (T25 L-wrench required). Use of a clutch-type rear derailleur is recommended.
PowerTrac Elliptical™ (PTE)
PowerTrac Elliptical rings feature 10 % ovality, combined with 112° timing, which is measured after the Top Dead Center (TDC). This means that with PTE rings, the larger-diameter section of the ring engages with the chain at the optimal point on the downstroke, or " Power Zone," to take advantage of your body's natural biomechanics.
So while your pedal stroke will feel smooth and natural, you'll get better traction and acceleration with PTE rings: It's like having two chainrings in one! Your pedal stroke is biomechanically weakest when your pedals are at the top and bottom of the circle (around 11:00-1:00 and 5:00-7:00 on a clock face), in what is called the " Recovery Zone" . The ovalized shape of PTE rings means has a smaller diameter when the chain engages in this section and will actually function as if you had TWO FEWER teeth - think of it as an instant gear change to an easier ring, say from a 34 t ring to a 32 t!
They work the same way in the Power Zone of your stroke - when your front pedal is between 1:00-5:00 in the clock analogy. Here, where your legs are their most powerful and efficient, the PowerTrac Ellipticals have a larger diameter and function like they have TWO EXTRA teeth, say from a 34 t to 36 t.
But how does this help traction? The above features combine to provide a smoother, more efficient pedal rotation. This provides steadier torque on the rear wheel, so you're less likely to over-pedal in the Power Zone and spin out. It also makes pedaling a bit easier during the Recovery Zone, so you maintain momentum. This " two-chainrings-in-one" effect keeps pedaling smooth and torque constant through each revolution.
Wolf Tooth has put countless hours into designing, prototyping, and testing to come up with their innovative new tooth profile. Test riders all over the world have confirmed that this design provides unparalleled performance. Here are the details of WHY it works: Notice that right side of the tooth has a very different shape than the left side. The right side of the tooth transmits force to the chain and the left side provides clearance for mud and debris. Since they have completely different functions it makes sense that they are designed differently. Extra strength where you need it, less material where you don't.
Notice that the right side of the tooth is as wide as Wolf Tooth can make it to maximize amount of area in contact. More area in contact means the load is spread over a larger area which in turn minimizes wear on the tooth. The left side of the tooth helps to guide the chain as it meshes with the chainring but it does not have to transmit any load. The left side of the tooth is narrower than the roller pin on the chain. Wear is not a concern on this side of the tooth so Wolf Tooth removed extra material to create a channel for mud to flow away. More clearance means less friction and less chance of mud causing a dropped chain.
Manufacturer Part Numbers:
28 tooth: OVAL-SDM28-BST
30 tooth: OVAL-SDM30-BST
32 tooth: OVAL-SDM32-BST
34 tooth: OVAL-SDM34-BST
- 1 x Wolf Tooth Components Elliptical Direct Mount SRAM Boost chainring
- black/28 tooth: 60 g
- black/30 tooth: 68 g
- black/32 tooth: 74 g
- black/34 tooth: 83 g