{"product_id":"sunrace-rd-m91-9-speed-rear-derailleur-long-cage","title":"SunRace RD-M91 9-Speed Mountain Bike Rear Derailleur - Long Cage","description":"\u003cp\u003e\u003cstrong\u003eA reliable and affordable 9-speed rear derailleur built for mountain bikes, recreational trail riding, and everyday drivetrain replacements.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eThe SunRace RD-M91 is a durable 9-speed mountain bike rear derailleur designed to deliver dependable shifting performance without the premium price tag. Featuring a long cage design and compatibility with wide-range cassettes up to 36 teeth, the RD-M91 is an excellent replacement for worn or damaged Shimano-compatible 9-speed drivetrains.\u003c\/p\u003e\n\n\u003cp\u003eConstructed from a combination of aluminum, engineered polymer, and steel components, the RD-M91 balances durability, performance, and affordability for riders who want reliable shifting on trails, bike paths, and daily rides.\u003c\/p\u003e\n\n\u003cbr\u003e\n\n\u003ch3\u003eKey Functional Details\u003c\/h3\u003e\n\n\u003cul\u003e\n\u003cli\u003eCompatible with 9-speed mountain bike drivetrains\u003c\/li\u003e\n\u003cli\u003eLong cage design supports wide-range gearing\u003c\/li\u003e\n\u003cli\u003eMaximum cassette size of 36 teeth\u003c\/li\u003e\n\u003cli\u003e45T total chain wrap capacity\u003c\/li\u003e\n\u003cli\u003eDirect mount derailleur installation\u003c\/li\u003e\n\u003cli\u003eAluminum mounting bracket for durability\u003c\/li\u003e\n\u003cli\u003eEngineered polymer and steel construction\u003c\/li\u003e\n\u003cli\u003eSuitable for recreational, trail, hybrid, and commuter bikes\u003c\/li\u003e\n\u003cli\u003eCost-effective replacement for many Shimano 9-speed systems\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cbr\u003e\n\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\n\u003cul\u003e\n\u003cli\u003eBrand: SunRace\u003c\/li\u003e\n\u003cli\u003eModel: RD-M91\u003c\/li\u003e\n\u003cli\u003eSpeed Compatibility: 9-Speed\u003c\/li\u003e\n\u003cli\u003eCage Length: Long Cage (SGS)\u003c\/li\u003e\n\u003cli\u003eMaximum Cassette Cog: 36T\u003c\/li\u003e\n\u003cli\u003eTotal Capacity (Chain Wrap): 45T\u003c\/li\u003e\n\u003cli\u003ePull Ratio: 2:1\u003c\/li\u003e\n\u003cli\u003eMount Type: Standard Direct Mount\u003c\/li\u003e\n\u003cli\u003eConstruction: Aluminum, Engineered Polymer, Steel\u003c\/li\u003e\n\u003cli\u003eColor: Black\u003c\/li\u003e\n\u003cli\u003eWeight: 342g\u003c\/li\u003e\n\u003cli\u003eUPC: 4710944242935\u003c\/li\u003e\n\u003cli\u003eManufacturer Part Number: RDM91.LD00.1S1.BX\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cbr\u003e\n\n\u003ch3\u003eCompatibility \u0026amp; Technical Notes\u003c\/h3\u003e\n\n\u003cul\u003e\n\u003cli\u003eCompatible with most Shimano-style 9-speed mountain bike shifters\u003c\/li\u003e\n\u003cli\u003eDesigned for use with 9-speed chains and cassettes\u003c\/li\u003e\n\u003cli\u003eSupports cassette sizes up to 36T\u003c\/li\u003e\n\u003cli\u003eDirect replacement option for many older Shimano 9-speed derailleurs\u003c\/li\u003e\n\u003cli\u003eCompatible with standard derailleur hanger-equipped frames\u003c\/li\u003e\n\u003cli\u003eAlways verify drivetrain speed before ordering\u003c\/li\u003e\n\u003cli\u003eProfessional derailleur adjustment may be required after installation\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cbr\u003e\n\n\u003ch3\u003eShimano Equivalent Models\u003c\/h3\u003e\n\n\u003cul\u003e\n\u003cli\u003eShimano RD-M430\u003c\/li\u003e\n\u003cli\u003eShimano RD-M390\u003c\/li\u003e\n\u003cli\u003eShimano RD-M370\u003c\/li\u003e\n\u003cli\u003eShimano RD-M280\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cbr\u003e\n\n\u003ch3\u003eService \u0026amp; Ownership Context\u003c\/h3\u003e\n\n\u003cul\u003e\n\u003cli\u003ePopular repair option for older mountain bikes and hybrids\u003c\/li\u003e\n\u003cli\u003eIdeal when replacing bent, worn, or damaged rear derailleurs\u003c\/li\u003e\n\u003cli\u003eProvides excellent value for riders restoring older bicycles\u003c\/li\u003e\n\u003cli\u003eWorks well with common 11-32T and 11-34T cassette setups\u003c\/li\u003e\n\u003cli\u003eReplacement derailleur hanger inspection is recommended when replacing a damaged derailleur\u003c\/li\u003e\n\u003cli\u003eRoutine cable and housing replacement can significantly improve shifting performance\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cbr\u003e\n\n\u003ch3\u003eFit \u0026amp; Use Signals\u003c\/h3\u003e\n\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eGood Fit:\u003c\/strong\u003e 9-speed mountain bikes, hybrid bikes, comfort bikes, recreational trail bikes, commuter bikes\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNot A Fit:\u003c\/strong\u003e 10, 11, or 12-speed drivetrains, SRAM Eagle systems, electronic shifting systems\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUse Case:\u003c\/strong\u003e Replacement derailleur, bike restoration, drivetrain repair, recreational riding, commuting\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cdiv data-ai=\"mechanic-insight\" style=\"display:none\"\u003e\n\n\u003cstrong\u003e1. Real Mechanic Insights\u003c\/strong\u003e\n\n- One of the most common derailleur replacements for older 9-speed mountain bikes.\n- Often purchased after a bike falls on the drivetrain side and bends the original derailleur.\n- Many shifting issues blamed on the derailleur are actually caused by worn cables, housings, or bent derailleur hangers.\n- The 36T cassette capacity works well for riders looking for easier climbing gears.\n- An excellent budget-friendly replacement for many Shimano Acera and Alivio level systems.\n\n\u003cstrong\u003e2. Typical Customer Searches\u003c\/strong\u003e\n\n- 9 speed rear derailleur\n- Shimano compatible derailleur\n- mountain bike derailleur replacement\n- SunRace RD-M91\n- long cage derailleur\n- derailleur for 11-36 cassette\n- replacement derailleur for hybrid bike\n\n\u003cstrong\u003e3. Often Replacing\u003c\/strong\u003e\n\n- Shimano Acera derailleurs\n- Shimano Altus derailleurs\n- Shimano Alivio derailleurs\n- Bent OEM derailleurs\n- Damaged entry-level mountain bike drivetrains\n\n\u003cstrong\u003e4. Good Fit \/ Not A Fit\u003c\/strong\u003e\n\n- Good Fit: Riders repairing older 9-speed bikes or upgrading from worn entry-level derailleurs.\n- Not A Fit: Modern 10-12 speed systems or electronic drivetrains.\n\n\u003cstrong\u003e5. Recommended Shop Pairings\u003c\/strong\u003e\n\n- 9-speed chain\n- Shift cable and housing kit\n- Derailleur hanger alignment service\n- Cassette inspection\n- Drivetrain tune-up\n- Rear derailleur hanger replacement\n\n\u003cstrong\u003e6. What Customers Compare This To\u003c\/strong\u003e\n\n- Shimano Acera RD-M3020\n- Shimano Alivio RD-M3100\n- Shimano Altus RD-M2000\n- MicroSHIFT Advent derailleurs\n- SunRace RD-M900 series\n\n\u003c\/div\u003e","brand":"SunRace","offers":[{"title":"Default Title","offer_id":53641766175034,"sku":"GG-DER-SUNRACE-RDM91-9SP-LONG","price":29.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0745\/5735\/8394\/files\/26881.jpg?v=1782231173","url":"https:\/\/gograva.com\/products\/sunrace-rd-m91-9-speed-rear-derailleur-long-cage","provider":"Grava Adventure Corporation","version":"1.0","type":"link"}