Gemini calls their new Rigel carbon ring the “most technologically superior chainring” to ever be made. And says it’s “actually the lightest chainring on the planet.” Crafted from steady fiber ‘cast’ carbon over an aluminum skeleton, the narrow-wide 1x Gemini Rigel carbon chainrings are stiff, long-wearing, even aero, plus in fact extremely light-weight.
Gemini Rigel carbon 1x MTB chainrings
We’ve seen a quantity of carbon and composite chainrings through the years. I even made a full carbon chainring for my singlespeed mountain bike greater than 2 a long time in the past that critically outlasted alloy rings. Carbon lightness and stiffness have been promising within the chainring division. However none have actually solved the problems of making sharp & advanced tooth from carbon that may deal with various chain angles, assist chain retention, and survive common put on and tear. Essentially the most profitable till now have resorted to creating the outer ring of tooth out of assorted metals. And limiting the carbon to structural reinforcement or a lighter spider design.
Till now…
Gemini crafts the Rigel direct mount chainrings largely from carbon, however with alloy on the chain’s contact floor with the chainring’s tooth.
Who’s Gemini once more?
We largely know Gemini Composites for his or her premium carbon mountain bike bars and 1-piece cockpits. Began in 2015 to develop superior carbon MTB elements by Roland Baides, a motorbike design engineer out of the Cero design studio. Baides turned the chief design engineer for Unno for the primary 2 years of the brand new mountain bike model, earlier than returning full-time to Gemini.
Now, located in a small industrial zone a 1/2 hour up the coast from Barcelona – on prime of auto restore & paint retailers – Gemini combines their design and carbon manufacturing in a single mixed studio and workshop. All the pieces from thought to elements, made in-house.
How is Solid Carbon made?
Gemini’s secret sauce is multi-part development, dubbed ‘Solid Carbon’, aka compression molding. First, a steady aluminum ring of hollowed-out 7075-T6 alloy is lower. Then, they sandwich the toothed ring between precision-cut prepreg carbon discs, pressed inside a mould, and heated, underneath greater than 100 tons of pressure to reach on the last shaping.
The true secret just isn’t completely revealed – however is patented. The element of how Gemini orients the fibers within the tooth. Based mostly on our understanding of the patent, the strain of molding squeezes the unaligned fibers (Discontinuous Fiber Composites just like what we all know as UD) within the precut carbon discs. This aligns the fibers concentrically (3 in Fig. 8-B), as they squeeze into the slim channels of the tooth within the mould.
Gemini says the result’s “a corporation of steady fiber construction within the tooth that’s unattainable with conventional carbon fiber manufacturing processes“.
Out of the compression mould, there’s nonetheless loads of hand ending to scrub up extra resin flash squeezed out. And to shine the completed Rigel ring.
Tech particulars
In keeping with Gemini, the ensuing Rigel is the lightest Direct Mount chainring accessible. They declare a weight of simply 39g for a 30T SRAM 3-bolt ring. “That is primarily due to using carbon fiber for each the construction and the tooth, regardless of having an inside steel core devoted solely to extending its lifespan.”
The Rigel rings in the end expose the perimeters of the interior alloy ring. That gives direct chain curler to aluminum contact, to switch pedaling masses via the carbon physique.
This implies long-term sturdiness in opposition to put on. On the identical time, the carbon sandwich reduces friction, quiets the chain, and improves the general aerodynamics of the system.
Gemini doesn’t explicitly state what number of miles or kilometers you possibly can anticipate to get out of their new carbon Rigel chainrings. However does advise cleansing & sustaining it like an everyday ring – ideally utilizing a dry chain lube. In addition they declare that actual circumstances sturdiness is successfully just like standard aluminum chainrings.
All are manufactured in Barcelona, Spain proper the place they had been designed and engineered.
Gemini Rigel carbon chainrings – Pricing, Choices & Compatibility
The brand new carbon Gemini Rigel chainrings appear surprisingly reasonably priced really. OK, at 125€ a bit, they aren’t low cost.
However loads of machined alloy direct mount chainrings already promote for 70-90€. That is formally cheaper than a inventory SRAM XX SL substitute chainring. Even a heavier, non-DM Carbon-Ti 1x chainring constituted of the same materials combine will set you again 181€.
Gemini limits choices to simply three tooth sizes in the interim, every with Enhance normal 3mm offset: 32, 34, or 36T. In the event you suppose you’re quicker than that, you’ll have to attend till Gemini develops greater rings…
Gemini has been coy with the main points, however prompt gravel-ready 38, 40, 42 & 44T rings will come “Quickly“, as will a 52/36T pair. And they’re additionally considering of oval rings, and a model for SRAM’s newest thread-on ring-around-a-powermeter.
Compatibility is huge, although. Gemini makes the carbon Rigel chainrings in 5 direct mount interface requirements – SRAM 3-bolt, SRAM 8-bolt, Shimano, RaceFace/Easton & Cannondale Hollowgram. That covers the overwhelming majority of direct-mount MTB crank arms on the market right this moment. They’re mentioned to work with 11 & 12-speed drivetrains from Shimano & SRAM, together with T-Sort Flattop chains.
Get them now, direct from Gemini.
