CeramicSpeed – makers of high-end, fast-spinning ceramic bearings to suit bottom brackets, headsets, wheel hubs and jockey wheels – has just announced it’ll be offering a new jockey wheel upgrade for watt-hungry riders using a SRAM Eagle 1×12 drivetrain.
Designed to replace the stock plastic 12t and 14t jockey wheels on an XX1, X01 or GX Eagle rear derailleur, the CeramicSpeed ‘Double 14-tooth Eagle Pulley Wheel’ set swaps in two 14t machined alloy jockey wheels that are designed to reduce drivetrain friction, while improving shift performance too.
Erm, so how do they do that?
According to CeramicSpeed (and one of its sponsored teams, Specialized Racing) the increase in jockey wheel diameter reduces the tight angle the chain has to pass through, thereby lowering friction. CeramicSpeed has been making jockey wheel upgrades for road bikes for quite a while, including those huge 17t jockey wheel sets designed for SRAM & Shimano road rear mechs. This mountain bike version isn’t quite that big, but CeramicSpeed is still stating a pretty generous reduction in drag;
“Our measurements show, that the watt saving when using 14/14-tooth compared to 12/14-tooth is 20% higher” explains CeramicSpeed’s R&D Manager, Carsten Ebbesen. “Furthermore, the improved shifting performance is a combination of a narrow-wide upper pulley wheel and a stiff aluminium design combined with the unique ceramic bearing with very little play.”
The jockey wheels themselves are made from either titanium or alloy, and house high quality bearings made in Denmark by CeramicSpeed. They use the narrow-wide tooth profile like the stock SRAM 1x jockey wheels, which is designed to interlock with the narrow-wide profile of the chain.
“As already proven by the OSPW system on the road, larger diameter pulley wheels reduce friction by limiting the amount of rotation experienced by each chain link as it passes. Combined with the precision machining and incredibly high quality bearings inside, the new 14/14-tooth Eagle pulleys are the final piece of drivetrain perfection to get the absolute most out of our mountain bike drivetrains. In addition, the machined alloy pulleys are stiffer and therefore enhance shifting feel and give a more precise and instant engagement than we have experienced with stock pulleys before”, explains Brad Copeland, mechanic at Specialized Racing.
We don’t have a confirmation on pricing, but they surely won’t be cheap. For SRAM 11-speed derailleurs, CeramicSpeed currently charges €199 for the alloy set, and €349 for the titanium set. Wowsers.
Then again, that’s still kind of cheap compared to CeramicSpeed’s €800 3D printed titanium jockey wheels…