--- product_id: 410537420 title: "Shadow Rear Derailleur - 10/11 Speed - SGS Long" brand: "shimano" price: "137986CFA" currency: XOF in_stock: true reviews_count: 8 category: "Shimano" url: https://www.desertcart.sn/products/410537420-shadow-rear-derailleur-10-11-speed-sgs-long store_origin: SN region: Senegal --- # Silent single tension spring 10/11-speed compatibility Durable alloy construction Shadow Rear Derailleur - 10/11 Speed - SGS Long **Brand:** shimano **Price:** 137986CFA **Availability:** ✅ In Stock ## Summary > ⚡ Shift like a pro, ride like you own the trail! ## Quick Answers - **What is this?** Shadow Rear Derailleur - 10/11 Speed - SGS Long by shimano - **How much does it cost?** 137986CFA with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.sn](https://www.desertcart.sn/products/410537420-shadow-rear-derailleur-10-11-speed-sgs-long) ## Best For - shimano enthusiasts ## Why This Product - Trusted shimano brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Snag-Free Confidence:** Direct cable routing keeps cables protected from trail hazards and unexpected snags. - • **Effortless Efficiency:** Durable 11T bearing pulleys reduce friction, maximizing your pedaling power. - • **Trail-Ready Durability:** Wide alloy links and pivot body engineered for rugged, long-lasting performance. - • **Whisper-Quiet Operation:** Single tension spring design eliminates chainstay noise for a stealthy ride. - • **Precision Shifting Mastery:** Optimized slant angle and strong return spring deliver flawless gear changes every ride. ## Overview The Shimano Shadow Rear Derailleur SGS Long is a high-performance 10/11-speed MTB component designed for smooth, silent, and reliable shifting. Featuring a low-profile Shadow RD design, durable alloy construction, and advanced cable routing, it supports up to 42T sprockets and a 41T cage capacity, making it perfect for serious riders seeking precision and durability on every trail. ## Description The Shimano Deore M4120 derailleur, featuring a low-profile Shadow RD design, excels in 2x10 and 2x11-speed MTB riding. It offers reliable shifting performance and durability. The Shadow design boasts a super low profile and optimized slant angle for smooth shifting. A single tension spring ensures a silent ride by preventing contact with the chainstay. Direct cable routing avoids snags from trail hazards. Wide alloy links and a pivot body are complemented by fluorine-coated link pin bushings. A strong return spring provides a positive shifting feel, while durable 11T bearing pulleys reduce friction. The top normal spring selects higher gears. Compatible with HG-X11 11-speed and HG-X 10-speed systems, it supports a max low sprocket of 42T (2x11/2x10-speed) and has a 41T capacity SGS cage. Review: Thumbs up - Sloved my issue. Great replacement. Review: Deore M4120 derailleur - I have been modifying a steel bike for light touring. Initially I installed this derailleur with an 11-36 10-speed cassette and a triple crank, but I wanted to simplify the drive train with a 46-30 and an 11-42. Although this combination exceeds the published chain capacity for the derailleur, it works quite well, with good chain tension, and able to reach all gear combinations, although I would never use it in 46/42. The derailleur cage rubbed slightly on the chain below the lower jockey wheel, but I bent it outward about one millimeter for clearance. It now shifts and runs quietly. ## Features - Dependable Shifting & Durability: Deore M4120 Shadow 10/11-speed Rear Derailleur - Super Light Shifting: Low Profile Shadow Design with Optimized Slant Angle - Silent Ride: Single Tension Spring Prevents Chainstay Contact - Snag-Free Riding: Direct Cable Routing for Trail Safety - Robust Construction: Wide Alloy Links and Pivot Body - Smooth Operation: Fluorine-Coated Link Pin Bushings - Positive Shifting: Strong Return Spring - Efficient Performance: Durable 11T Bearing Pulleys for Low Friction - Higher Gear Selection: Top Normal Spring - Compatibility: HG-X11 11-speed and HG-X 10-speed - Max Low Sprocket: 42T for 2x11/2x10-speed - Cage Capacity: 41T SGS Cage ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B089KBWD9P | | Best Sellers Rank | #660,889 in Sports & Outdoors ( See Top 100 in Sports & Outdoors ) #695 in Rear Bike Derailleurs | | Brand | SHIMANO | | Brand Name | SHIMANO | | Case Material Type | Alloy Steel or Aluminum | | Color | Black | | Customer Reviews | 4.6 out of 5 stars 46 Reviews | | Global Trade Identification Number | 04550170621124 | | Item Dimensions L x W x H | 6"L x 5.25"W x 3.5"H | | Item Weight | 0.93 Pounds | | Manufacturer | Shimano | | Manufacturer Part Number | ERDM4120SGS | | Material | Aluminum | | Material Type | Aluminum | | Model Number | ERDM4120SGS m | | Mount Type | Clamp-On Mount | | Mounting Type | Clamp-On Mount | | Number of Teeth | 11 | | Product Dimensions | 6"L x 5.25"W x 3.5"H | | UPC | 192790621128 | ## Product Details - **Brand:** SHIMANO - **Color:** Black - **Material:** Aluminum - **Item Weight:** 0.93 Pounds - **Mounting Type:** Clamp-On Mount ## Images ![Shadow Rear Derailleur - 10/11 Speed - SGS Long - Image 1](https://m.media-amazon.com/images/I/614ui-70cGL.jpg) ## Customer Reviews ### ⭐⭐⭐⭐⭐ Thumbs up *by B***5 on April 8, 2026* Sloved my issue. Great replacement. ### ⭐⭐⭐⭐⭐ Deore M4120 derailleur *by K***R on September 27, 2024* I have been modifying a steel bike for light touring. Initially I installed this derailleur with an 11-36 10-speed cassette and a triple crank, but I wanted to simplify the drive train with a 46-30 and an 11-42. Although this combination exceeds the published chain capacity for the derailleur, it works quite well, with good chain tension, and able to reach all gear combinations, although I would never use it in 46/42. The derailleur cage rubbed slightly on the chain below the lower jockey wheel, but I bent it outward about one millimeter for clearance. It now shifts and runs quietly. ### ⭐⭐⭐⭐⭐ Perfecto *by F***Z on April 11, 2024* Desviador trasero estupendo. Todo en su caja original y funciona perfecto y compatible con cassette y desviador de 10v 11-42. Muy conforme. No puedo decir nada de la durabilidad porque lo instalé recién hace un mes, pero aparenta un material shimano bueno como debe ser. ## Frequently Bought Together - Shimano Deore RD-M4120 Rear Derailleur - 10-11 Speed - SHIMANO SL-M6000 Deore Shift Lever, Band-on, 10-Speed, Right Hand - KMC X10-116L, NP/BK 10 Speed Bicycle Chain --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.sn/products/410537420-shadow-rear-derailleur-10-11-speed-sgs-long](https://www.desertcart.sn/products/410537420-shadow-rear-derailleur-10-11-speed-sgs-long) --- *Product available on Desertcart Senegal* *Store origin: SN* *Last updated: 2026-05-16*