{"product_id":"gemini-ogle-aero-carbon-pulley-wheels-sram","title":"Gemini Ögle Aero Carbon Pulley Wheels + Ceramic Bearings  — SRAM","description":"\u003cp\u003e\u003cstrong\u003eOversize pulleys that drop into your stock cage.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eEvery other oversize pulley system asks you to replace the entire derailleur cage — a $400 to $700 proposition that adds parts, adds weight, and changes how your derailleur behaves.\u003c\/p\u003e\n\n\u003cp\u003eÖGLE doesn't. Each version is sized to the largest tooth count your stock cage will accept without modification. You get the bigger pulleys, the ceramic bearings, and the friction reduction, using the derailleur you already own.\u003c\/p\u003e\n\n\u003cp\u003eHandcrafted in Barcelona. Available for SRAM Eagle Transmission 12-speed, Red\/Force\/Rival 12-speed, and Red\/Force\/Rival XPLR 13-speed.\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003ch4\u003eWhere the friction actually is\u003c\/h4\u003e\n\n\u003cp\u003eA rear derailleur loses power in two places, and ÖGLE targets both.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eBearing drag.\u003c\/strong\u003e Stock pulleys typically run basic sealed steel bearings or plain bushings. ÖGLE uses hybrid bearings — ceramic balls in steel races. Ceramic balls are rounder, harder, and lighter than steel, which means less rolling resistance, particularly at the high rotational speeds a small pulley sees.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eChain articulation angle.\u003c\/strong\u003e Every link has to bend as it wraps a pulley and straighten as it leaves. The smaller the pulley, the sharper that bend, and every bend costs energy. Going oversize opens the angle each link travels through, so the chain flexes less to do the same job.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eHonest about the magnitude:\u003c\/strong\u003e the mechanism is real, but oversize pulleys and ceramic bearings are a watts-in-single-digits upgrade, not a transformation. Anyone promising you more than that is selling. What you'll actually notice on the first ride is how much quieter the drivetrain runs.\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003ch4\u003eCarbon body, aluminum teeth\u003c\/h4\u003e\n\n\u003cp\u003eSame construction principle as Gemini's RIGEL chainrings, and it answers the obvious objection to a carbon pulley.\u003c\/p\u003e\n\n\u003cp\u003eEach tooth has a \u003cstrong\u003e7075-T6 aluminum core\u003c\/strong\u003e underneath — that's the surface the chain actually contacts and wears against. Carbon fiber is molded continuously around it, with the fibers oriented to follow the tooth profile rather than being cut across it.\u003c\/p\u003e\n\n\u003cp\u003eThat continuous molding is the difference between this and the alternatives. It isn't injection-molded fiber-filled plastic, and it isn't carbon machined from a block — both of those sever the fibers and lose the strength that made carbon worth using. Here the fiber runs unbroken around each tooth, so the structure is carrying load the way carbon is supposed to.\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003ch4\u003eClosed, spokeless design\u003c\/h4\u003e\n\n\u003cp\u003eMost pulleys are spoked, with open gaps between the hub and the teeth. Those gaps let grit, mud, and road spray straight into the bearing area.\u003c\/p\u003e\n\n\u003cp\u003eÖGLE is fully enclosed — no spokes, no openings. Debris stays out of the bearings, the profile is cleaner through the air, and the pulley integrates visually with the derailleur instead of looking bolted on.\u003c\/p\u003e\n\n\u003cp\u003eThe assembly is finished with black anodized aluminum end caps, which set bearing preload correctly and keep the whole unit sealed.\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003ch4\u003eWeight\u003c\/h4\u003e\n\n\u003cp\u003eComplete sets, bearings and caps assembled, run between 22 and 29 grams depending on tooth configuration.\u003c\/p\u003e\n\n\u003cp\u003eContext matters here. That's roughly comparable to the stock plastic pulleys you're removing — the weight story isn't against stock. It's against the alternative upgrade: machined aluminum oversize pulleys from the established aftermarket brands run 40 to 50 grams, and full cage-replacement systems add considerably more than that.\u003c\/p\u003e\n\n\u003cp\u003eSo you're getting oversize pulleys and ceramic bearings without the weight penalty that usually comes attached to them.\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003ch4\u003eWho makes it\u003c\/h4\u003e\n\n\u003cp\u003eGemini Composites is a small Barcelona workshop founded in 2015 by Roland Baides, a design engineer who spent two years as chief design engineer at Unno before returning to Gemini full time. Design, engineering, and carbon production happen under one roof.\u003c\/p\u003e\n\n\u003cp\u003eThe pulley program came out of more than three years of development and over 500 prototypes, using the same forged carbon process behind their chainrings.\u003c\/p\u003e\n\n\u003cp\u003eEvery set is made by hand. Production is limited to what that workshop can produce.\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003ch4\u003eChoosing your version\u003c\/h4\u003e\n\n\u003cp\u003eMatch the version to your rear derailleur, not to your cassette or your frame.\u003c\/p\u003e\n\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eEagle Transmission 12-speed\u003c\/strong\u003e — for SRAM T-Type Eagle Transmission derailleurs. The hangerless ones that bolt directly through a UDH frame.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRed \/ Force \/ Rival 12-speed E1\u003c\/strong\u003e — for SRAM's 12-speed road AXS rear derailleurs.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRed \/ Force \/ Rival XPLR 13-speed\u003c\/strong\u003e — for SRAM's 13-speed XPLR gravel rear derailleurs.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eThese are not interchangeable. Tooth counts and spacing differ between them, and a set intended for one will not perform correctly on another.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eIf you're unsure which derailleur you have,\u003c\/strong\u003e look at the model name printed on the cage, or count the cogs on your cassette — 13 means XPLR, and a derailleur with no hanger between it and the frame means Transmission.\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003ch4\u003eCompatibility\u003c\/h4\u003e\n\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDrivetrains:\u003c\/strong\u003e 1x11, 1x12, 1x13, 2x11 and 2x12\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCage:\u003c\/strong\u003e Fits stock derailleur cages — no aftermarket cage required\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBearings:\u003c\/strong\u003e Hybrid, ceramic balls in steel races\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003chr\u003e\n\n\u003ch4\u003eSpecifications\u003c\/h4\u003e\n\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eConstruction:\u003c\/strong\u003e Forged carbon molded continuously around 7075-T6 aluminum tooth cores\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBearings:\u003c\/strong\u003e High-precision hybrid with ceramic balls\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEnd caps:\u003c\/strong\u003e Black anodized aluminum\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDesign:\u003c\/strong\u003e Fully enclosed, spokeless\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSet weight:\u003c\/strong\u003e 22.2g (12\/14) · 23.9g (12\/16) · 25.1g (14\/16) · 29g (14\/20)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFinish:\u003c\/strong\u003e Natural forged carbon\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOrigin:\u003c\/strong\u003e Handcrafted in Barcelona, Spain\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty:\u003c\/strong\u003e 3 years\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003chr\u003e\n\n\u003ch4\u003eInstallation\u003c\/h4\u003e\n\n\u003cp\u003eStraightforward, and no chain length change is needed. Pull the cage back to take up chain slack, swap the pulleys, and torque the mounting bolts to your derailleur manufacturer's spec.\u003c\/p\u003e\n\n\u003cp\u003ePay attention to pulley orientation and to which one goes where — the upper and lower pulleys are not identical, and installing them reversed will make shifting worse rather than better.\u003c\/p\u003e\n\n\u003cp\u003eOnce mounted, fine-tune with your derailleur's micro-adjust rather than assuming the indexing carried over unchanged.\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003ch4\u003eLiving with them\u003c\/h4\u003e\n\n\u003cp\u003eKeep them clean and run a dry chain lube where conditions allow. Dry lube pulls less grit into the tooth interface and the bearing seals, which is what determines how long any pulley lasts.\u003c\/p\u003e\n\n\u003cp\u003eThe bearings are sealed and don't require regular service. If the drivetrain starts sounding less smooth than it did, that's usually a chain-wear problem before it's a bearing problem — check the chain first.\u003c\/p\u003e\n\n\u003chr\u003e\n\n\u003cp\u003e\u003csmall\u003e\u003cem\u003eRIGEL, ÖGLE, and Gemini are trademarks of Gemini Composites S.L. SRAM, Red, Force, Rival, AXS, XPLR, Eagle, and Transmission are trademarks of SRAM LLC. State Bicycle Co. is not affiliated with or endorsed by SRAM LLC. Specifications subject to change without notice.\u003c\/em\u003e\u003c\/small\u003e\u003c\/p\u003e","brand":"Gemini","offers":[{"title":"SRAM - 12speed E Generation Road (Rival \/ Force \/ Red)","offer_id":44183476764759,"sku":"751503808579","price":186.0,"currency_code":"GBP","in_stock":true},{"title":"SRAM - 12speed Eagle Transmission MTB","offer_id":44183476797527,"sku":"751503808562","price":186.0,"currency_code":"GBP","in_stock":true},{"title":"SRAM - 13speed XPLR Gravel (Rival \/ Force \/ Red)","offer_id":44183476830295,"sku":"751503808586","price":186.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0232\/3305\/files\/GeminiOgleAeroCarbonPulleyWheels_CeramicBearings_SRAM-1.png?v=1787350157","url":"https:\/\/www.statebicycle.com\/en-gb\/products\/gemini-ogle-aero-carbon-pulley-wheels-sram","provider":"State Bicycle Co.","version":"1.0","type":"link"}