I wouldn't bother replacing it until there's an actual reason to. If it's looking very worn (pointy cogs), or you're getting chain skip, go ahead and replace it, but if it's working as intended, I'd just ride it until it isn't. (Personally, I've ridden a _much_ cheaper SRAM SX cassette for more than 1,000 miles and had zero issues with it, so I'd be pretty surprised if X01 needed replacing after 600 miles, but who knows).


Im currently at 2100 miles on my GX and still going strong.


Chain maintenance is a big part. Lubing and cleaning the chain often helps everything. Changing the chain before it’s 0.75% worn is a big part too. A worn chain wears a cassette faster. And if your biking in dirty muddy winter conditions vs. nice dry conditions affects west too. [Here](https://cyclingtips.com/2019/12/the-best-bicycle-chain-durability-and-efficiency-tested/) is a great article on chain wear and durability.


>I wouldn't bother replacing it until there's an actual reason to. Mine looked worn and replaced it recently after 6 years. And O man, the difference it made. Paddling became so much easier that its crazy.


Drivetrain wear starts with the chain. If you get a chain wear indicator and replace the chain every time it exceeds .5 on the indicator (and before it reaches .75), then you should be able to use the same cassette through several chains and thousands of miles.


This is the right answer. Better to throw a $40 chain on your bike than replace an XD cassette. I generally get about 3 chains per cassette if i stay on top of it


[There is a pretty good argument for going with a SRAM X01 chain for value $/km](https://cyclingtips.com/2019/12/the-best-bicycle-chain-durability-and-efficiency-tested/) (skip to the graphs near the bottom of the article).


For an X01 cassette this is definitely the way to go. They can last several thousand miles if you replace the chain as soon as it starts to show wear. The pinned cassettes from sram I have not had great luck with (usually end up bent before they get worn out) but the X01 and XX1 cassettes last a really long time if you keep them happy. You'll know to replace the cassette when a new chain starts skipping.


My indicator only has 0.75 and 1.0 😭


I replace my cassette when it no longer works with a new chain. By this I mean when you install a new chain, and it skips under load in gears you use frequently. This is more likely to happen if you use the same chain for too long.


Then you throw on a slightly worn chain and keep. Sending it!


Ride lower spec and replace when you feel like it because it's so cheap😎


I think an average cassette lasts 3 chains. If your chain has trouble sitting on 1st or 2nd gear-like the teeth don't quite match up and it hovers-time for a new chain. If a new chain has issues, you probably need a new cassette. If you don't replace your chain quick enough, the chain wears out the cassette, too. A chain usually lasts about 50 rides for me. This year, I'm on 2nd cassette and 4th chain.


This isn’t an average cassette. It’s machined out if a solid block of hardwearing steel and covered in a hardwearing coating. I’ve got an x01 cassette from 2016 that’s only just worn through the coating. That’s over six chains and god knows how many thousands of miles. For reference I get about 18 months out of a XT / GX cassette.


Sick!! Not a bad run!!


I don't think I can tell based on how many chains I've gone through, as I've had to replace my chains from damage, rather than wear. Is that a common issue with GX chains? I've snapped mine 4 times in the last month or two. And my previous chain got bent past usability. My chain hovers a tiny bit, but it still pedals fine


4 times over a couple months shouldn’t be happening… Has this happened while pedaling uphill? If so, you might need to work on uphills with downshifting sooner and/or increased pedal power.


Happened twice while sprinting, but I had already gotten into gear. Happened once while I was easy-pedaling through a parking lot, and once while keeping a steady cadence up a hill. I feel like either GX chains are weak, or mine was defective. I've had a kmc chain on my other bike and I've had absolutely no issues with it


why are you running GX on an X01 cassette? You’re correct that GX is garbage though


The chain I replaced a couple days ago had stretched more than 1cm from spec over 3 feet of chain. I hang all the old chains on a nail, and compare the stretch against a new one. I don't break them, usually, just strech out of spec. They will still work alright, but a stretched out chain is dragging the cassette down with it. Sometimes, the master link blows up under power while shifting.


Dam you and your mixed units


Very scientific, lol! I think metric mm works better than the whole 7/64 of an inch stuff. Measuring jumps? Feet. Shooting? Yards. Speed of light? M/s. Boating? Knots. Almost a mm? That's a scodotch!


I always called that last one a cunt hair




They kind of suck from my experience. Try a KMC chain


Got a KMC on my other bike. Never had an issue, and bonus, I can reuse the masterlink


Dude no, use an X01 or XX1 chain. You should be able to get nearly 1500 miles out of an X01 (speaking from experience), and more out of an XX1. You have an insanely nice cassette, you’ll shorten its lifespan by putting chains that wear more quickly on it.


I always say 3 maybe 4 chains if you really replace your chain right when it starts to “stretch”


Replace when needed. Keep an eye on chain stretch though as a stretched chain will reduce the life of ur cassette and chainring.


If you're replacing chains before they're too stretched, a high quality cassette should last you at least several seasons. Keeping it clean will also extend its life. That said, some cassettes have aluminum rings that are softer and wear quicker (Shimano XT 12 speed comes to mind). Cassette rings can also become bent or have broken teeth from an impact and should be replaced at that point. It really depends on the cassette. I have an all steel 11 speed SRAM GX cassette that has been going since 2016 and has thousands of miles on it but I also had to replace a Shimano 12 speed cassette after one season because a the 46t alloy ring wore out.


ride it until it gives you trouble. i tend to get around 1200 miles out of a GX cassette.


Clydesdales wear out drivetrain components the fastest but average size/weight riders should see 1000 or more miles on a cassette. Personally, my X01 cassette has 2500 miles or more on it.


My GX cassette had over 10k miles when I replaced it.


Cassettes can last anywhere from 500 to over 10k miles. X01 cassettes are very durable. Why do you think it's time to replace? What chain lube do you use?


I got about 3.5K miles out of my GX Eagle cassette and i think it was 3 chains.


I've had LBS tell me to replace my cassette on virtually brand new bikes. Imo, it's all a racket for the bike industry. If it isn't perceptibly affecting you're riding, then I wouldn't worry about it. I've ridden motorcycles missing actual teeth on the sprockets and not noticing it. I think prophylactically replacing cassettes on a pedal bike is unnecessary unless you're insane or a roadie.


I've ridden cassettes missing teeth - but that's not the same as worn teeth. If the LBS doesn't show you why they think the cassette should be replaced, then ask. The failure mode was listed above - chain begins to skip under heavy load.


40 hrs. No noticeable drawbacks when I pedaled. Buying a $100 part every 40 hours is a racket. That, or you're 300 lbs doing speedway with your MTB \[in muddy sand\].


Agree with you. 40 hours is maybe 400 miles (+/-)... and unless you ground through some slog and the chain was covered in mud... it shouldn't have worn out. \#1 place is check chain wear. My GX lasted \~1,800 miles and 2 GX chains and it was kept fairly clean (our trails aren't open when it's too wet, so mud isn't a big issue). Symptom was chain skipping under heavy load (basically pushing hard up a hill, which is just the suck).


yep just talked to local shop owner and a local guy has 3,500 miles on his trek rail all on the same cassette(chain replaced as needed)


When it’s worn out


Another cheap trick is to use a different chainring so you end up using different cassette rings to make things last a little longer. Doesn't work well in mountains where you use the whole cassette, but if you're a more or less flatlander and use just 2-3 cassette rings most of the time, and those 2-3 get worn out, then change your chainring so you use the 2-3 ones above / below those 3 you wore out. Again, this is a cheap trick that would work in a pinch, and you could end up with a really bad gearing setup... you'd also need to jump about 4 teeth up front.


If you don’t replace chain in time, new chain on old worn cassette will skip then it all needs to be replaced.


In my opinion, the cassette must have really bad ware or damage of some sort. I have an XO1 cassette and it’s been 2 years and solid to keep going I still haven’t changed my chain (XO1 chain) and still holding up. As long as you stay on top of maintenance AND most importantly, know how to shift, these parts can last quite some time.


Replace your chainring most frequently. Then your chain. Then the cassette.


Too many variables. Hours and miles on the trail can't be used as a guide. The only real answer is you need to be able to tell when things are worn out.


You guys replace your cassettes?!


I just replaced my 12 speed GX last weekend. I never fully degrease my drive train and only lube it maybe once every five rides are so. i use rock n roll gold so it’s kind of a cleaner and lube. stuff rocks! I usually replace my chain once it shows stretch, but I didn’t bother so I ran my original drivetrain for almost 3 years with just under 4000 miles. finally broke a few teeth off my 50t and then the 40t started slipping as well. maybe X01 won’t be as durable as GX but i would bet you should get like ~2000 to 3000 miles out of it.


I replace my chains every 2000 km or so and the last cassette had to go after 4700 km of dirt, sand and mud (convert to Fahrenheit and gallons at your own leisure). SRAM makes some excellent stuff.


X01 lasted me about 2500 miles of singletrack. Costs more, replace less.


I got 3000+ miles on my GX cassette and that too needed to be replaced because I forgot to change the chain on time a few times.