SRAMGX Eagle Rear Derailleur - 12-Speed, Long Cage, 52t Max, Lunar

Super price and a well built spring and pulley system.SRAM quality n great looks are evident, shifting and chain smoothness is so smooth on my mtnbike. Easy to install.

Two years ago I bought a Diamondback Sync'r which came equipped with 12-speed SX Eagle. It never shifted particularly well and had a severe chain slap problem. At the urging of my bike mechanic brother in law, I bought this derailleur and also a GX shifter and installed them on my bike. Night and day difference. Shifting is crisp and smooth even under load, and the chain slap is totally gone. Can't recommend this enough as an upgrade from SX. For a reasonable price it'll make your bike run better than ever.(Note that I kept the original SX/NX cassette and it works perfectly well with the GX derailleur.)

I wasn’t very inpressed with the SX derrailleur in my Bigfoot. The thinh just broke after little use and without using it very well. Warranty claim and new SX lasts even less... Read I was not the only one but then I found that many “solved” the problem by upgrading. Got another bike with thr gx group and so far I loved this derrailleur. So replaced my sx with this, everything is cross compatible and once you do this change you will love your bike again. Still hate Sram for making sx but this... makes me understand why manh love them. Great derrailleur, buttery smooth, easy to install, comes with the chain gap tool and you can swap the thing real quick. 100% recommended, worth the upgrade 100%.

Replaced an NX derailleur that I destroyed. The improved performance over the NX was well worth the small price difference. Shifting is much crisper with the GX and it is 100% compatible with an NX cassette

This GX derailleur might weigh a tiny bit more than a more expensive version, but it works just as well and is more durable. These SRAM derailleurs eventually stop shifting to the top gears well because their springs are weak, which is disappointing, but there's no reason to spend extra money on the ones marketed as higher-end models.

The GX derailleur works great on my 2021 Giant Trance X 29 3. It had an SX derailleur 12spd on it and it just wasn't shifting correctly. I swapped the shifter and derailleur to GX and even though it has an NX 12 spd cassette which is on an HG hub, it works like it was designed specifically for it! Once I dialed in the B-adjustment with the white tool and the bike set for 30% sag it was shifting perfectly. It's probably the most crucial step. Otherwise you set it up right on the stand and then it shifts poorly once you're in the saddle. A tip on setting your sag, get on the bike and see where the rear shock rests, then take the air out of the shock, use your body weight on the seat to push the bike to that 30% position, hold the white tool with one hand tight against the jockey wheel, and adjust the screw with the other hand. Once those arrows line up it set and you never have to worry about it again. It's much easier to do by yourself than the tutorials make it out to be.Unfortunately someone between the seller and shipping broke the seal on the box. Which sucks because the box doesn't just hold itself closed and the derailleur was just bouncing around in the box rubbing up against the paperwork and the cardboard cover, which took a very small amount of paint off. I know I will damage it much worse some day, but come on, for a new product that is pretty disappointing. Since this was my second attempt at ordering this thing and having to wait for a refund from a product that was stuck in shipping purgatory, I decided to swallow my pride and just use it.It feels very solid, when it shifts it happens quickly and decisively, no more waiting around and listening to the chain grind around. I have ridden around town, but haven't taken it on the trail yet, but so far it seems quieter when dropping off of things

Glad to have another in the repair bin this last season!

I bought the entire GX groupset minus the cassette individually, because I wanted use an NX cassette so I didn't have to replace my hub to XD. Installed all the components and everything works superbly.I had no install issues because I did the necessary research and measurements. You should know your bottom bracket type and measurements, if you are boost or non-boost, which spacers you use and where (all information is available at SRAM) take a digital caliper and measure. Just make sure you watch the videos how to install these products before you purchase the components and try to install the wrong one. Be sure you have a new high quality derailleur hanger. This is not a first time beginner undertaking. Know when you have no idea and ask someone and if you don't know or don't have the right tools, take it to a bike shop. You will need a chain whip, and the right socket and tools to remove your existing cassette, and bottom bracket, and same for installing your bottom bracket. I used an SRAM DUB BSA boost+ bottom bracket 68/72mm. I lucked out because it had the correct spacer for the right side, plus the boost spacer I didn't need.