We won't try to convince you that elliptical (or oval, the same thing) chainrings will change your life...but they might! What we can say for sure is that they have a different feel from round rings and can provide an efficiency benefit and smoother power output for some riders. Testers report the biggest benefits on punchy singletrack and hills, allowing less shifting and faster acceleration.
The proprietary design has ovality of 10% and timing of 112° after TDC (top dead center). These values provide the benefits of an oval ring without the drawbacks of greater ovality or more aggressive timing. The simplest way to explain how they "feel" is that where your pedal stroke is weakest it feels like you have a 2 teeth less on the chainring and where you have the most power it "feels" like you have 2 more teeth. Example: a 34t chainring feels like a 32t in the weak part of your pedal stroke and a 36t in the part of the stroke where your legs have the most power.
These are Elliptical SDM (TM) direct mount chainrings for SRAM GXP crank and BB30 Long Spindle cranksets with removable spiders. This 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 (TM) chainring. We recommend using a T25 L-Wrench like this one or similar for removal and installation of the bolts.
SDM chainrings fit on SRAM cranksets with removable spiders: S2200, S2210, X9, X0, X01, XX1, X1 1400, Truvativ AKA Cranksets (GXP version), and newer S1400 (or X7) . If the crankarm and the spider are all made from the same piece of aluminum it is not removable. If you are planning to use this on an X9 or XX1 fat bike crankest, check out this explanation of chainline and hub spacing.
- Chainline is 50mm.
- All chainrings feature our Drop-Stop tooth design and are made from 7075 Aluminum
- Use a 10 or 11 speed chain. If using a 9 speed drivetrain, plan to use a 10 speed chain (it will shift fine), as the 9 speed chain fits too loosely on the ring.
- A T25 Torx wrench is required to remove the bolts that secure the the chainring or spider to the crankarm. An L-wrench works best since the crank spindle may contact a socket adapter and prevent it from engaging properly.
- Designed and manufactured in the USA!
- Product weights: 26t - 52g, 28t - 59g, 30t - 65g, 32t - 70g, 34t - 75g, 36t - 81g