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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
$ 209.00

Score By Feature

Based on 191 ratings
Customer service
9.55
Delivery
9.45
Satisfaction
9.36
Giftable
9.37

OveReview Final Score

How Our Score Is Calculated

Product Description

Shifting is quick and smooth, and the design is low-profile.
The efficiency of large 13T pulleys is improved.
Reduced low-gear tension and a bumper add to the drivetrain's quietness.
Rear gearbox with 12 speeds.

Questions & Answers

I had a slx 1x12 derailleur before, and I'm wondering if I can just swap it out for this one. ?

The XT 12-volt battery can be used. As a replacement for the SLX version, there is now a speed RD version. No issue. It's important to note that they're both 12 years old. speed.

Why does the description say it's for a 45-tooth cassette, but the answers to the questions say it'll work for 51 teeth as well?

There are two types of passators: 1x12 for 51T and 2x12 for 45T, and I'd buy one of each.

Is this up to the task of handling a ten-person group? Is it possible to get a cassette with 51 teeth and 12 speeds?

Yes, I'm using it on a 10-inch screen right now. 51, with one extra as a back-up.

Is this compatible with a friction shifter?

I'm sure it will, to be honest. But that's like asking if you can be pushed down the road by people on the outside of the car if you're sitting inside it. Yes, but it is preferable to purchase an older 7 or 8-inch model. For $20 on Ebay, I got a speed derailleur. These will work far better with a friction shifter and will cost you $90 less because they were designed to handle larger jumps.

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

This is the best derailleur I've ever used
5/5

This derailleur is absolutely incredible. Shifting is fantastic, and there is no skipping. br>br>A Shimano slx 11-speed shifter and 11-speed derailleur are used with this 12 speed derailleur. SunRace cassette number 51.

Ruby Hoffman
Ruby Hoffman
| Mar 11, 2021
Shifting is excellent
3/5

However, the item was damaged upon arrival. First and foremost, I installed the derailleur because my old one was broken and, as any mountain biker knows, I "needed" to ride; the broken piece was more of a nuisance than anything else. Inside the box, there was a separate bag for the broken lever switch part. (pic 1). It was clearly a broken piece, and I quickly identified the source of the break. I didn't want to have to wait another two weeks for a replacement. It shifts well once installed, and it arrived sooner than expected, to their credit. This, however, did not break during transportation. Was this an item that was returned but not examined? I dunno.

Veronica BYRNE
Veronica BYRNE
| Jul 09, 2021
Strong, precise, and dependable are three words that come to mind when thinking about this product The XT derailleur from Shimano is of exceptional quality
5/5

Precision, smoothness, and strength are all qualities that can be found in this product. It takes a lot more abuse than the XTR ones, in my opinion. The only caveat is that you must perform clutch maintenance, such as cleaning it once in a while and applying waterproof grease (instructions can be found on YouTube).

Carolina BARLOW
Carolina BARLOW
| May 08, 2021
Quality that is on par with performance! Bullet- This Shimano component is a great 'bang for your buck' purchase thanks to its foolproof design and flawless manufacturing
5/5

This is my second one (this one is for my new bike), and the first one I bought has given me 750 miles of trouble-free service.

Allie Maxwell
Allie Maxwell
| Jul 14, 2021
It shifts effortlessly
5/5

My Kona's drivetrain was changed from 1x10 to 1x12. The xt derailleur shifts smoothly and performs admirably when shifting on an incline. I strongly advise you to upgrade.

Kase Ross
Kase Ross
| Nov 11, 2021
SGS 1x12 XT Derailleur is extremely hard to come by
5/5

YUP! SGS 1x12 XT Derailleur with a truly long cage! Thank you very much! You were the only ones who had it on hand. I can't think of anything else to ask for. It does exactly what it says on the tin.

Bear Orozco
Bear Orozco
| Feb 22, 2021
It was well worth the money
5/5

My Deore derailleur was replaced with an XT derailleur, and the shifting is now more precise and crisp.

Angela Robbins
Angela Robbins
| Jul 21, 2021
Keep the speed at 11 if possible
3/5

Shimano 12 speed is far more finicky and unreliable than Shimano 11 speed in my experience.

Halle Haney
Halle Haney
| Dec 10, 2021

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