Home Page

Cart, contains 0 items

When autocomplete results are available use up and down arrows to review and enter to select. Touch device users, explore by touch or with swipe gestures.
Expert Help
Earn Rewards
  • Just In
  • Learn

XT BR-M8120 Disc Brake

5 out of 5 stars
3 Reviews
Current price: $183.99 - $206.99 Original price: $229.99
Up to 20% off



Why We Like The XT BR-M8120 Disc Brake

Here at the shop we have a saying that brakes only slow you down, and while we throw around the saying in jest, the truth of the matter is that only the best brakes are capable of stopping you on a dime. Shimano brakes have received universal praise for doing just that for years, and the XT BR-M8120 Disc Brake doesn't fail to impress with its quick-stopping power. With the launch of the new Shimano 8100 series we see some improvements made to the 8120 brakes, but largely they stay the same. You'll see the same 4-piston design for intensely strong stopping power and its improved heat dissipation over the 2-piston model, plus the same lever shape and integrated master cylinder, but with the addition of an extra 10% stopping power over the 8000-series brakes, and reduced rotor noise. The narrow clamp makes for a tidier cockpit to play well with remote lockouts and dropper posts, plus its compatible with the new I-SPEC EV design to save you more space on the bars.

While lighter riders rolling in smoother XC conditions may benefit from the featherweight XT 8100 series brakes, riders who are heavier and more aggressive riders who transition between trail and enduro riding will covet the increased power and modulation of the 8120 when things get steep, technical, and rowdy. Shimano opted to refine the brake levers we saw previously with the 8000 series, with updated Servo-Wave technology to match up with the next generation of I-Spec EV Rapidfire Plus shifters, with two-way release, instant release, and multi-release that offers more control and confidence in your modulation. Unlike previous models, the new 8100-series brake lever is built for both the 8120 and 8100 calipers, allowing your cockpit to feel the same when you transition from your all-mountain rig to your XC rocket. This new clamp features a more inboard clamp position modeled after the 9100 series, creating an extra point of contact between the bar and lever for increased efficiency and control, while minimizing its impact on cockpit real estate.


  • Shimano's popular trail brake ups braking power and modulation
  • 4-piston stopping power offers quicker braking than 8000 series
  • Predictable modulation allows for precise braking
  • The ceramic pistons reduce heat build-up
  • Finned pads further dissipate heat
  • Clamp designed based on XTR for better bracing, I-Spec EV compatibility
  • The pre-bled lever/caliper/hose assembly is ready to install
  • Item #SHIU18H
Lever Adjustability
tool-less reach adjust, free-throw
Mount Type
mineral oil
not included
metal pads
Claimed Weight

Overall Rating

5 based on 3 ratings

Review Summary

1 Stars - 0 reviews
2 Stars - 0 reviews
3 Stars - 0 reviews
4 Stars - 0 reviews
5 Stars - 3 reviews

Fits True To Size

Screen reader users: the following list provides a visual scale to illustrate the product fit. Please refer to the heading above for the fit type in text.
Runs smallTrue to sizeRuns large

What do you think about this product?


Selecting an option will reload the available reviews on the page
5 out of 5 stars

February 25, 2024

They set the Standard

I've used it several times
Size Bought:
Front and rear
6' 1"

Had them for a month and the 4 piston brakes are great on the E-bike. Shimano's work great but not the easiest with cables/hoses running through the frame. I had to bleed a few times.

5 out of 5 stars

October 24, 2020

Replacement Pads

I've put it through the wringer

What's up with Shimano these days? Because I love these brakes. But I would love them much more if I could find replacement pads for them. They are non-existent...

Gary C

Originally reviewed on Backcountry.com

5 out of 5 stars

October 23, 2020

Use these to stop

I've put it through the wringer

I love these brakes...XT works just fine, no need to buy XTR.

Mike N

Originally reviewed on Backcountry.com