[Closed] Cassette trashed after first chain even though wear guage isn't >75%

measure the chain properly. Checker is just a quick guide and you should check it properly once in a while. I rotate 2 chains every few rides which lets me properly clean, lube and measure one chain and have it ready to fit should I have a need to chain one quickly - failure or grit for example. Also stretches out the wear.

Never bothered with anything special with chains but try and change early. Pop the old chain on and run it into the ground.

Get a steel rule and measure 12 pairs of links. Anything over 12 1/8" means it's worn. It could be that your gauge isn't very accurate.

What about the chainrings? I've swapped cassettes and chains before and had similar issues to you, only to realise that the soft alloy chainrings were ronnied and were causing the slippage.

Agree with both the above - either rotate often and early, or stick to one chain & cassette and run them into the ground together, but in the past where I've waited until .75% wear like you, it's been too late to put a new chain on the old cassette.

Get a steel rule and measure 12 pairs of links. Anything over 12 1/8" means it's worn.

Anything above 12 1/16" (which is 0.5% wear) and you'll be wearing out your cogs. If you wait until 0.75% as with the OP that's too late to save the cogs.

It's a false economy to wait longer anyway - by 0.5% wear the hard coating has worn off and you get far less than twice the mileage by waiting until 1%.

.I rotate 2 chains every few rides

Out of interest how do you get a reliable joint when removing/refitting so often?
Are you using new quick links every time?
9spd? Or 10/11?

I do the same as Andyl. I use 10sp Shimano chains with KMC links, and re-use the link each time - that's what they're for.

I can't speak for andy, but I use quick links which are designed to be reused on my chains (9 & 10 speed, though I'm fairly sure the 10 speed ones I use are also available for 11)

You've got a new chain on a slightly worn cassette, that's your problem. The cassette is perfectly fine and will last a long time yet but only if you continue with the worn chain or similarly worn chain.

The problem is when people buy into the Park Tools wear indicator stuff and start replacing chains way too early and then it's a gamble as to whether it will mesh with the cassette. Early enough maybe, but usually I find it won't.

I've experimented with this. I used to do the replace chain early technique. I was buying chains every few months and likely a new cassette with it anyway or maybe a couple of chains.

I now just let it all run on, and chain and cassette are lasting a couple of years with no problems vs every 6 months for the whole lot before. I was basically chucking away perfectly good components.

The only issue is if you actually break the chain enough that you have to replace it, then you need a new cassette. KMC chain plus the use of quick links if you rarely snap one and it's rarely if ever an issue.

Oh and yeah, chainring will wear. It will wear whether it's a new chain or old. Same with cassette. In my opinion the whole replace your chain early else you'll wear your components is BS, and I've proven it to myself.

Other thing is often people think the cassette is shot because things start skipping, but 9 times out of 10 I've found it's the indexing is out and/or gear cable needs sorting out.

It's not a directional chain issue is it? I know the new Shimano chains are directional ie only fit one way and the opposite way doesn't work right. Also the quick links can be fitted the wrong way too and cause jumping. Probably not the cause in your case but worth checking.

I find the smallest cog on the latest XT cassette wears before all the others and starts to jump which is odd as you would think the most wear would be on the biggest cogs. I found you can buy the smallest cog separate so bought half a dozen for not a lot.

Also the teeth on XT cassettes can look weird ie some jagged, some normal some worn but as long as they still work I just keep on going and stick a new chain on now and then.

not got into that chain rotation stuff but does make sense - i use a chain checker on a regular basis and....

[hobbyhorse]mrs antigee's 10speed used pure on road 1500-2000km max chain life cleaned by me prob twice maybe more in that[/hobbyhorse]

convinced that 10speed(+) chains and hence cassettes are just a consumable with short lives - rarely used to see broken chains at the road side but common now

Im not convinced by chain rotation either. I wear chain and casette down to the ground until both need replacing, which tends to be once a year for my milage and riding conditions. I never have any issues with chains slipping and the first sign i get if ive left it a bit late is if the chain snaps (when i know its already way past the 1.0 stage). A few of my riding mates on the other hand are convinced they are saving money by changing the chain every couple of months, and inevitably now and again they will have left it too long and the new chain skips on the old casette which means they fork out on a new casette too

Get a steel rule and measure 12 pairs of links. Anything over 12 1/8" means it's worn.
Anything above 12 1/16" (which is 0.5% wear) and you'll be wearing out your cogs. If you wait until 0.75% as with the OP that's too late to save the cogs.

It's a false economy to wait longer anyway - by 0.5% wear the hard coating has worn off and you get far less than twice the mileage by waiting until 1%.

Was it an extra 1/16"? I've got a 600 steel rule with green and red makes for measuring mine. Took the measurements from Sheldon Brown and extrapolated for increased accuracy.

Pop the old chain on and run it into the ground.

Best advice in the whole thread.