Shimano XT Di2 Shadow Plus RD-M8150-12 12-speed E-bike Rear Derailleur - black/long

Shimano XT Di2 Shadow Plus RD-M8150-12 12-speed E-bike Rear Derailleur

Item number: 92142

The XT Di2 RD-M8150-12 12-speed rear derailleur from Shimano for e-bikes with Hyperglide+ drivetrain

RD-M8150-12 is an electronically controlled 12-speed rear derailleur from the Shimano XT-Di2 series and is used on E-MTBs with EP801 or EP6 motor and Hyperglide+ drivetrain. It cannot be used for bicycles without one of these motors. The rear derailleur was designed for 1x groupsets and HG+ cassettes with 51 teeth on the largest sprocket. It gets its energy directly from the e-bike battery and impresses with the Free Shift technology, which gives you a more dynamic cycling experience. Free Shift means that you can shift while freewheeling, i.e. without pedalling, which makes cornering and descending easier and allows for more aggressive, controlled riding.
As a Shadow Plus rear derailleur, RD-M8150-12 is not only compactly built, it also comes with an integrated chain stabiliser that prevents chain slap even on rough surfaces and thus counteracts chain drops. Despite the higher torques on e-bikes, the gear shifts are fast, smooth and reliable. In this way, the rear derailleur integrates perfectly with the precise and race-proven Hyperglide+ drivetrain. Since it is largely made of aluminium, it also weighs only about 375 grams. Sealed bearings on the tension and guide pulleys extend the service life. The connection to the Di2 E-bike System is established via the newer EW-SD300 cable type.

Information regarding the return of batteries and electrical equipment:

Information on the return and disposal of batteries and electrical equipment can be found here.

Guidelines for Replacing E-bike Components:

Before you replace components on your e-bike, please read through the guidelines for component replacement for CE-marked e-bikes/pedelecs with pedal assistance.


Deore XT Di2 M8150
All Mountain
Shimano MTB 12-speed
Compatibility - Chains:
HG 12-speed

Technical Information:

Derailleur Pulleys:
Outer Cage Material:
Inner Cage Material:
Other Materials:
aluminium, composite material (GFRP), steel, stainless steel


Power Cable:
EW-SD300 (1 x connection)
SW-M8150-R, SW-M8150-IR, SW-EM800-L, SW-EN600-R
Cassette (10-51 T):
CS-M9101-12, CS-M9100-12, CS-M8100-12, CS-M7100-12, CS-M6100-12
CN-M9100, CN-M8100, CN-M7100, CN-M6100
  • EP8 EP801 for MTB
  • EP6 for MTB


  • electronic rear derailleur optimised for E-MTBs with 1x12-speed drivetrain (Hyperglide+) (EP801 or EP6 motor required)
  • perfect integration of the drivetrain technology with the e-bike system components and the intelligent electronic shifting system
  • Free Shift function allows shifting without pedalling for more dynamic, controlled riding
  • fast and smooth shifting despite the higher torques on e-bikes
  • race-proven, precise performance
  • flat design prevents snagging
  • chain stabiliser (Shadow+) prevents the chain from banging and jumping off and promotes smooth running
  • direct power supply via e-bike battery (STEPS), connection via EW-SD300 cable
  • E-Tube project ensures firmware updates
  • three fluorine-coated joint bushings
  • derailleur pulley bearings sealed
  • painted cage


Digital Integrated Intelligence (Di2)
Di2 systems are the electronic shifting systems from Shimano. They are based on the SEIS, the Shimano Electronic Intelligent System, which takes over the index shifting function from the mechanical components, only via power cables or radio signals and not via a Bowden cable. Shifting is done by simply pressing a button. This has the advantage that no great effort is required, your concentration on the ride is not disturbed and operation is easy even with cold hands. In addition, the electronic gear changes are very fast and highly precise. There is also no risk of a defective circuit due to dirty cables or other problems. You can adjust individual settings via the E-Tube Project, such as adjusting the shifting speed, the number of shifting operations per button press or the Synchro or Semi-Synchro shifting function. Shimano offers an app for this purpose. Gear maintenance and firmware updates are also done via E-Tube, with the bike connected to a PC running the appropriate E-Tube software for more extensive workshop work.

Shadow RD+
Shadow Plus rear derailleurs are just as low-profile as Shimano's Shadow rear derailleurs. In addition, a stabilizer with on/off switch is used to reduce chain slap and thus counteract chain drop. At the same time, this results in a quieter drive. Weight is also saved compared to other chain restraint devices.

Free Shift
The Free Shift technology for e-bikes with Shimano motors of the EP8 and EP6 series gives you the possibility to change gear without pedalling. This is a big advantage, especially when descending and cornering, because you can concentrate completely on your body position, your line and your flow. Free Shift therefore benefits bike control, stability and riding enjoyment. When the descent is over or at the exit of the corner, you are in the right gear and don't have to struggle with gears that are too hard or too easy. The technology takes advantage of the fact that when coasting there is just enough engine power to perform a gear shift without slowing the bike down.


Cage Length:
Max. Largest Sprocket Teeth:
Min. Largest Sprocket Teeth:
Max. Smallest Sprocket Teeth:
Min. Smallest Sprocket Teeth:
Max. Chainring Difference:
Total Capacity:
Manufacturer Number:


  • 1 x Shimano XT Di2 RD-M8150-12 Shadow Plus rear derailleur


  • black/long: 375 g
  • 100 day return period
  • Online since 1998
  • Trusted Shop 4.85 / 5.00


  • black/long, sold out

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