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SHIMANO XT RD-M8100-SGS RD-M8120-SGS Rear Derailleur - 12-Speed, Long Cage, Black SHIMANO XT RD-M8100-SGS RD-M8120-SGS Rear Derailleur - 12-Speed, Long Cage, Black SHIMANO XT RD-M8100-SGS RD-M8120-SGS Rear Derailleur - 12-Speed, Long Cage, Black SHIMANO XT RD-M8100-SGS RD-M8120-SGS Rear Derailleur - 12-Speed, Long Cage, Black

SHIMANO XT RD-M8100-SGS RD-M8120-SGS Rear Derailleur - 12-Speed, Long Cage, Black

SHIMANO XT RD-M8100-SGS RD-M8120-SGS Rear Derailleur - 12-Speed, Long Cage, Black SHIMANO XT RD-M8100-SGS RD-M8120-SGS Rear Derailleur - 12-Speed, Long Cage, Black SHIMANO XT RD-M8100-SGS RD-M8120-SGS Rear Derailleur - 12-Speed, Long Cage, Black SHIMANO XT RD-M8100-SGS RD-M8120-SGS Rear Derailleur - 12-Speed, Long Cage, Black
$ 118.99

Score By Feature

Based on 149 ratings
Delivery
9.54
Value for money
9.28
Customer service
9.26
Packaging
9.80

OveReview Final Score

How Our Score Is Calculated

Product Description

The shifting is fast and shock-free, and the profile is low.
Efficiency is increased by using large 13T pulleys.
Drivetrain silence has been improved by reducing tension in low gear and adding a bumper.
There is a 12-speed rear gearbox.

Questions & Answers

The manufacturer of this derailleur states that it can be switched with another model of slx 1x12 derailleur. Is this true?

If you have an XT 12-inch, you can use it As a replacement for the SLX version, speed RD is available. This is not a problem. One thing they have in common is that they are both 12-year-olds It is fast.

Is that because in the description it says that it works for a 45 tooth cassette but in the answers it says that it can also work for 51 teeth?

For 51T there are 12 pins of one type and for 45T, there are 12 pins of another type, so I would pick the correct pin for each one.

What is the compatibility of this with friction shifters?

Yeah, I have no doubt However, it would be equivalent to asking if if you were sitting in a car can people on the outside of it push you down the road. Can be done, but it is best to buy a newer 7 or 8 instead- On Ebay, you can get a speed derailleur They will be far more effective with a friction shifter because they were designed to handle bigger jumps. The cost of those is

What is the maximum number of teeth this device can hold?

This is likely to be the case. A Shimano M8000 derailleur can handle a cassette with a diameter of 50T without any problems. Due to the fact that it was made for 51T, a 52T cassette should be a piece of cake for this. The length of the chain should be read in the instructions. The chain is used more extensively with these derailleurs. It uses 2 to 4 links more than any other derailleur. When you have an 11-speed system, you will speed up Whether it is a speed shifter or not. However, the 12 speed set is a definite plus- I appreciate it!)

Selected User Reviews For SHIMANO XT RD-M8100-SGS RD-M8120-SGS Rear Derailleur - 12-Speed, Long Cage, Black

Easily one of the best derailleurs I have ever used! I am in awe of this derailleur! There are no skips at all and the shifting is amazing
5/5

With this 12 gear derailleur you need to use a Shimano SLX 11 speed shifter and 11-speed ring and cassette. This cassette is part of the 51 SunRace series.

Niko BEVAN
Niko BEVAN
| Jan 03, 2021
You made a good shift
3/5

It was broken when it was shipped. As a matter of fact, I went ahead and installed the derailleur since my old one was broken and as a mountain biker I "needed" to ride. The broken piece is more of a hassle than anything else. Within the box, there was a separate bag for the broken lever switch piece. Here is a screenshot of (1). My first thought was that it must have been a broken piece, since I found where it was broken from right away. A new one would be available in 2 weeks and I didn't want to wait another 2 weeks for it. As soon as it was installed, it worked very well, and it shipped sooner than expected, to their credit. In any case, it didn't break in transit. Did this product not receive a thorough inspection after being returned? It's not that important to me.

Noe Carson
Noe Carson
| Jul 19, 2021
This is a strong, precise and reliable product
5/5

There is simply no competition in terms of quality for Shimano's XT derailleur. This is a very precise, smooth and strong verb. As far as I can tell, it can take more abuse than an XTR one. Taking care of the clutch is the only thing you have to do, be sure to clean it once in a while and apply some waterproof grease (check out instructions on Youtube for more info).

Nathaniel ROBSON
Nathaniel ROBSON
| Mar 17, 2021
This derailleur is hard to find with SGS 1x12 XT drives
5/5

You got it! One of the best long cage SGS 1x12 XT derailleurs around! Your help is much appreciated! There was only one stockist of it you guys were the only ones. I'm not sure what more you can ask for. What it says on the box is true!.

Calliope Wise
Calliope Wise
| Jan 19, 2021
OK, good to know
5/5

This derailleur is new and in its original.

Keith Singleton
Keith Singleton
| Jul 05, 2021
I am happy with the results
5/5

A fantastic product that I would strongly recommend. I have converted my bike from 3x7 to 1x12.

Alberto Day
Alberto Day
| Nov 10, 2020
This is excellent! I am very pleased with this result
5/5
Dior Beck
Dior Beck
| Jan 16, 2021
It is a great derailleur, though the clutch may get sticky
3/5

My derailleur has been used about 740 miles so far. As far as it works, it works great - but about 250 miles and 700 miles, the clutch on my unit "stuck" and the cage stayed in the down position when shifting to a harder gear or smaller Putting these two things together created a huge amount This can be resolved by disengaging the clutch (flipping the lever to the off position) at the trailside. The cam stabilizer (item 7) and the back end of the plate axle (item 10) need to be greased to fix the problem if you experience the same issue. In fact, I have done this twice now and the second time I was greeted by a bunch of black gunk that appeared to have built up on the cam unit and strap (I neglected to take a picture). Since ordering a replacement cam unit and stabilizer, my problem is fixed. We can only hope that these solutions will address the issue.

Malani McCormick
Malani McCormick
| Dec 19, 2020

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