Name: Shimano XT RD-M8120-SGS Rear Derailleur - 12-Speed Long Cage Black For 2x
Brand: Shimano
SKU: IRDM8120SGS
Price: 145.0 USD
Availability: InStock

Shimano XT RD-M8120-SGS Rear Derailleur - 12-Speed Long Cage Black For 2x

$145.00

Shipping calculated at checkout.

Free Domestic shipping

In stock, ready to ship
Backordered, shipping soon

Deore XT RD-M8100 Rear Derailleur

Offers fast and shockless shifting thanks to HYPERGLIDE+ technology

The low-profile design includes a bumper added to the derailleur pulley cage

Shimano Shadow RD+ technology reduces chain slap and creates a quieter drivetrain

Includes large 13t pulley

Drivetrain is silent in all gear positions with decreased rear derailleur and chain tension in low gear

Largest Cog	45
Color	Black
Rear Der/Shifter Compatibility	Shimano Mountain
Rear Derailleur Mount Type	10x1 Standard
Drivetrain Speeds	12
Weight	284
Chain Wrap Capacity (teeth)	45
Cage Length	Long
Drivetrain Compatibility	12-Speed 2X

Shipping Policy

Components:

All component items (wheels, drivetrains, suspension, brakes, etc.) ship within 1–4 business days of purchase.

Bicycles:

Complete bikes typically ship within 2–3 weeks due to build, tuning, and inspection times. You will receive tracking information as soon as your order is ready to ship.

Riding Gear & Apparel:

Riding gear and apparel orders (helmets, jerseys, gloves, etc.) ship within 1–3 business days.

Returns & Exchanges:

If you received the wrong size or wish to exchange an item, it must be returned in original condition—unused, uninstalled, and with all packaging intact.

For full details, please see our Refund Policy before initiating a return.

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Every bike that leaves our shop is more than just a machine—it’s a promise of quality. From the moment you choose your ride, our expert team gets to work, hand-building and prepping each bike with precision. We meticulously inspect every component, fine-tune the details, and run thorough safety checks to ensure everything is dialed in perfectly. Because when you hit the road or trail, you deserve a bike that’s ready for anything.

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At SpokeX Bike Co., bikes aren't just our business — they’re our way of life. As a rider-owned and operated shop, every decision we make comes from firsthand experience on the trail, at the race, and on the open road. We know what it’s like to chase a new line, push through the pain cave, and celebrate the ride — because we live it every day.

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I recently ordered a set of custom spokes from SpokeX Bike Co., and I couldn’t be more impressed. The customer service was absolutely outstanding. This crew truly understands the importance of communication and customer care.
During my order, they ran into an unexpected hiccup when their paint gun malfunctioned. Instead of leaving me wondering, they immediately reached out to explain the situation and kept me updated every step of the way. The delay was only two days, and my order was quickly completed and shipped right after.
What really stood out was their attention to detail and genuine interest in my bike setup. After describing the color combination of my bike, wheels, and new rims, they suggested pink powder-coated spokes with blue nipples, and wow, what a perfect recommendation! The result looks incredible.
If you’re looking for quality craftsmanship, honesty, and a team that goes above and beyond for their customers, SpokeX Bike Co. is the place to go. I highly recommend them for your next custom bike project… these guys are the best in the business!

These guys were great to work with. Hooked me up with a great deal on my new Transition Regulator CX. Great communication and shipped fast.

Shimano XT RD-M8120-SGS Rear Derailleur - 12-Speed Long Cage Black For 2x

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