The Shimano RD-RX815 Jockey Wheel Set (also shared with the Ultegra R8000 series) is the premium "High-Grade" pulley solution designed specifically for 11-speed drivetrains that demand reliability in harsh conditions. Whether you are racing a coastal criterium or navigating a corrugated gravel track in the Wheatbelt, these pulleys provide the mechanical precision required for Shimano’s Shadow RD+ stabilized derailleurs.
Unlike entry-level pulleys that rely solely on bushings, this set utilizes a Sealed Precision Cartridge Bearing in the lower tension pulley. This reduces rotational drag and ensures the pulley spins smoothly even when coated in dust or mud. The upper guide pulley features a high-quality ceramic bushing and Shimano’s Centeron lateral float, allowing for a tiny amount of side-to-side movement that ensures the chain perfectly finds the cog during every shift, even if your cable tension is slightly off.
Sealed Bearing Tension Pulley: The lower pulley features a sealed internal bearing, providing significantly lower friction and better longevity than standard bushing-style pulleys.
Ceramic Bushing Guide Pulley: The upper pulley uses a specialized ceramic bushing for high-heat resistance and consistent "float," critical for precise 11-speed indexing.
Shadow RD+ Optimization: Specifically designed to handle the increased chain tension and vibration of clutched (stabilized) rear derailleurs.
Mud-Shedding Profile: The tooth geometry is carved to self-clean during rotation, preventing the buildup of "gunk" that can lead to chain skip or noisy operation.
High-Strength Composite: Constructed from a glass-fiber reinforced resin that is incredibly resistant to the abrasive wear of sandy or gritty environments.
While these are the "stock" replacement for the GRX Di2 series, they are the go-to performance upgrade for almost all Shimano 11-speed road and gravel derailleurs:
| Pulley Set Model | Series / Speed | Compatible Rear Derailleurs (RD) |
| RD-RX815 / R8000 | 11-Speed Gravel | RD-RX815 (GRX Di2), RD-RX817 (1x Di2) |
| RD-RX810 / R8000 | 11-Speed Gravel | RD-RX810 (GRX Mech), RD-RX812 (1x Mech) |
| Ultegra R8000 | 11-Speed Road | RD-R8000, RD-R8050 (Di2) |
| 105 R7000 Upgrade | 11-Speed Road | Can be used as a performance upgrade for RD-R7000 |
Gravel & Adventure Riders: If you are running a GRX 800-series drivetrain, these are the exact factory-spec replacements designed to handle off-road vibration and dust.
Performance Upgraders: A perfect, cost-effective upgrade for Shimano 105 (R7000) users who want to replace their standard bushings with a smoother-rolling sealed bearing.
Di2 Users: Essential for maintaining the near-instantaneous shifting speed of electronic drivetrains, which rely on zero-flex pulleys to move the chain precisely.
12-Speed Users: These are specifically spaced for 11-speed chains. If you are running the newer R8100 or RX820 12-speed groupsets, you must use the specific 12-speed pulley sets.
Standard Commuters: If your bike is a "beater" for short trips, the 105 R7000 Standard Pulleys offer similar durability at a lower price point.
When installing the RX815 pulleys, take a close look at the bolts. Because these are often used on "clutched" gravel derailleurs, the chain tension is much higher than on a standard road bike. We recommend a tiny drop of blue (medium) threadlocker on the pulley bolts to ensure they don't vibrate loose on corrugated gravel roads. Also, remember the Upper (Guide) and Lower (Tension) pulleys are not interchangeable—the Lower pulley has a directional arrow that must point in the direction of the chain's travel!
