{"id":1896767,"date":"2026-04-22T16:17:57","date_gmt":"2026-04-22T13:17:57","guid":{"rendered":"https:\/\/analyse.optim.biz\/?p=1896767"},"modified":"2026-04-22T16:17:57","modified_gmt":"2026-04-22T13:17:57","slug":"new-sram-s-series-debuts-udh-half-mount-drops-lighest-weight-mechanical-derailleur","status":"publish","type":"post","link":"https:\/\/analyse.optim.biz\/?p=1896767","title":{"rendered":"New SRAM S-Series debuts UDH Half Mount, drops lighest-weight mechanical derailleur"},"content":{"rendered":"
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SRAM is reorganizing their mountain bike drivetrain offerings under a new S-Series, and the shakeup promises to \u201cmake your choices easier.\u201d Though this mostly means fewer<\/em> choices for buyers, SRAM is<\/em> bringing a bit of new tech at the lower end, along with mostly lower prices. The new designation also attempts to separate legacy, non-UDH drivetrains from incompatible Eagle Transmission offerings.<\/p>\n

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SRAM XX1 derailleur left, S200 right.<\/figcaption><\/figure>\n

Lightest mechanical derailleur offerings are collapsed into mid-tier Eagle S200 group<\/h2>\n

SRAM is replacing their XX1, X01, and GX derailleurs with a single new derailleur known as S200. The S200 derailleur features a Type 3 clutch and is compatible with 10-50T and 10-52T cassettes. SRAM says this is their \u201cworkhorse\u201d S-Series derailleur.<\/p>\n

At $135, the S200 derailleur is priced the same as a GX derailleur, which suggests it will feature similar materials and construction. This means buyers will no longer have the choice of a more premium mechanical derailleur like the XX1, which featured a carbon outer cage and titanium bolts, and was priced significantly higher at $323. The XX1 derailleur weighs about 20g less than GX, and it\u2019s unknown how the weight of the S200 derailleur will compare to these two legacy options. Singletracks has reached out to SRAM to learn the weight of the S200 derailleur, but did not receive a reply as of press time.<\/p>\n

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Beyond the S-Series, SRAM\u2019s highest-level mechanical derailleur becomes the Eagle 90 Transmission derailleur, priced at $210. It\u2019s more robust than previous GX and XX1 derailleurs, and also significantly heavier by 100g+. Looking outside the SRAM ecosystem, weight-conscious component buyers might consider moving to the mechanical Shimano XTR derailleur, which weighs about 240g.<\/p>\n

The S500 derailleur is electronic, and cheaper than the AXS derailleurs it replaces<\/h2>\n

At the high end of the S-Series, the S500 derailleur is electronic and is priced at $390 (battery not included). That\u2019s $40 cheaper than the GX Eagle AXS that it replaces, and $440 less expensive than the XX1 Eagle AXS derailleur. Still, it\u2019s unclear whether the S500 derailleur is closer to the GX- or XX1-level in terms of performance and weight. In terms of pricing, though, it\u2019s cheaper than both.<\/p>\n

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SRAM Eagle S100 Drivetrain.<\/figcaption><\/figure>\n

Shorter crankarm length options and lower prices<\/h2>\n

With the move to S-Series, SRAM is adding shorter crankarm options across the board \u2014 down to 155mm \u2014 to fit more riders. Finding 155mm cranks was hit or miss among SRAM\u2019s previous groupset offerings. GX only went down to 165mm, while XX1 buyers could only choose from 170mm or 175mm lengths. SRAM\u2019s least expensive crankset, SX, did<\/em> offer a 155mm length.<\/p>\n

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SRAM notes the entry-level S100 group will be OE-focused, though it does appear many, if not all, of the components<\/a> will be available for purchase after market as well. Pricing is generally the same or lower for components across all three S-Series levels. For example, the MSRP for the mid-tier S200 crankset is $100 compared to $160+ for a GX Eagle crankset. The price of the entry-level PG-1210 cassette remains the same as before.<\/p>\n

\"Illustration<\/a><\/figure>\n

UDH Half Mount makes entry-level derailleurs more robust<\/h2>\n

SRAM\u2019s full, direct-mount derailleur interface makes Transmission derailleurs extremely durable and robust. Though none of the S-Series derailleurs are direct mount, and none require<\/em> a Universal Derailleur Hanger (UDH) interface, SRAM is introducing a Half Mount option for the entry-level S100 derailleur that takes advantage of UDH-compatible frames.<\/p>\n

The UDH Half Mount basically clips onto a nub on the S100 derailleur, adding extra bracing to the outside of the derailleur. SRAM says the Half Mount protects against \u201cincidental knocks and bumps\u201d while a Full-Mount rear derailleur has the added benefit of protecting against \u201ctrailside impacts and crashes.\u201d<\/p>\n

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Curiously, the S200 and S500 derailleurs are not Half Mount-compatible.<\/p>\n

What does this mean for Eagle Transmission drivetrains?<\/h2>\n

For now, the Eagle Transmission lineup remains the same. S-Series and Transmission components are generally incompatible, requiring a UDH-compatible frame. Though some Transmission components are backward<\/em> compatible with S-Series Drivetrain parts, SRAM notes with few exceptions, \u201cyou must use all Eagle Drivetrain or all Eagle Transmission components for the best performance and to preserve your warranty.\u201d<\/p>\n

Though the move is meant to simplify the two drivetrain lines, SRAM is not consistent in their own marketing materials, using \u201cEagle Drivetrain\u201d and \u201cEagle S-Series Drivetrain\u201d interchangeably. Not only that, SRAM was already using a similar S-Series designation for their OEM-only Transmission drivetrain, S1000<\/a>. They\u2019ve also used S-number designations for road components<\/a>, like the double-chainring S-650 Eagle crankset.<\/p>\n

Select SRAM Eagle S-Series Drivetrain components are available for purchase now from online retailers like Worldwide Cyclery<\/a>.<\/p>\n

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SRAM is reorganizing their mountain bike drivetrain offerings under a new S-Series, and the shakeup promises to \u201cmake your choices easier.\u201d Though this mostly means fewer choices for buyers, SRAM is bringing a bit of new tech at the lower end, along with mostly lower prices. The new designation also attempts to separate legacy, non-UDH […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[226,274],"class_list":["post-1896767","post","type-post","status-publish","format-standard","hentry","category-uncategorized","tag-crawlmanager","tag-singletracks-com"],"_links":{"self":[{"href":"https:\/\/analyse.optim.biz\/index.php?rest_route=\/wp\/v2\/posts\/1896767","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/analyse.optim.biz\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/analyse.optim.biz\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/analyse.optim.biz\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/analyse.optim.biz\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1896767"}],"version-history":[{"count":0,"href":"https:\/\/analyse.optim.biz\/index.php?rest_route=\/wp\/v2\/posts\/1896767\/revisions"}],"wp:attachment":[{"href":"https:\/\/analyse.optim.biz\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1896767"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/analyse.optim.biz\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1896767"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/analyse.optim.biz\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1896767"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}