Spotlight: SLF Motion Evo Speed System oversized rear derailleur pulley cage

Friction-cutting oversized pulleys, ceramic bearings, and real carbon fiber construction.

by James Huang

photography by James Huang


Spotlight is a new series on CyclingTips we’re using to briefly showcase new products we’ve just received, and/or products that require just a short review. This regular and short-form tech coverage replaces our previous Tech Round-Up series.


Berner pioneered the idea of oversized rear derailleur pulleys a decade ago, and while CeramicSpeed may have popularized the idea for the (well-heeled) masses with its OSPW, plenty of imitators have popped up since.

One of the nicer-looking ones we’ve encountered is the Evo Speed System from SLF Motion, which features CNC-machined aluminum oversized pulleys (14-tooth upper, 18-tooth lower), coated hybrid ceramic cartridge bearings, and true made-in-USA carbon fiber cage plates to maintain stock stiffness and shift performance. 

Somewhat surprisingly, SLF Motion doesn’t provide any efficiency claims on its site, although if they’re comparable to CeramicSpeed, users can expect drivetrain friction savings somewhere in the neighborhood of 2-4 watts. That said, it’s perhaps worth noting that Luke Plapp recently used the company’s Evo Aero oversized pulley cage system during his winning Australian men’s elite time trial national championship, and given the attention to detail paid to his bike setup, one would hope that he did his homework here as well.

Given CeramicSpeed’s substantial head start in this category, you might think that SLF Motion’s pulley cage system would be substantially less expensive. Truth be told, it’s far from cheap with a retail price of US$495, although it comes with a six-year warranty and still undercuts the equivalent CeramicSpeed version by US$154. 

SLF Motion offers the Evo Speed in a variety of configurations for Shimano, SRAM, and Campagnolo fitments, and in six different anodized pulley colors. If you’re feeling particularly flush, there’s even a version with 3D-printed titanium pulleys for a whopping US$895.

Price: US$495 (international prices based on current exchange rate)

Weight: 75 g (29 g heavier than stock)

More information: www.slfmotion.com

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