[Closed] 0.5% Chain Wear - Replace Chain Or Still Ok?

I aim for 0.75 and have never had a problem with stuff slipping. Although that's 3x9 mtb chains.
0.5 sounds like changing it a bit prematurely, but won't do any harm apart from to your wallet.

Change at.75

.5 is fine

Strange, in the intervening weeks I've checked wear once a week. Today, the mechanic checked it using his fancy tool with the multiple intervals and button thingy and I'm now at 0.758. Mechanic says the fixed length checker can be inaccurate at times. Looks like it's chain replacement time now.

Cassette's given me over 5000km so could change it, and mechanic advises changing it too. However, I'm in a bit of a skint period so could do with not changing it. Any advice?

Advice?

Change your chain when you get a detectable mechanical problem with it instead of believing all that rubbish about chain checkers...

Not a believer in prevention being better than cure? 🙂

You're onto something though. There aren't any problems with the transmission at the moment. However, I'm in the process of acquiring parts for a singlespeed build. Anything that comes off the road bike will go on the SS pile.

curiousyellow - Member
Cassette's given me over 5000km so could change it, and mechanic advises changing it too. However, I'm in a bit of a skint period so could do with not changing it. Any advice?

Change the chain if you think it needs it.
Ride bike.
If you get no slippage, carry on.
If the chain slips on the cassette, replace the cassette.

When you say, then mechanic checked it.....have you taken the bike into a shop for a chain change and potentially a cassette change?
It's a really simple job to do and worth getting the tools for. Will save you money in the long term.

There is a chain of thought that says run it till it starts slipping and change everything at once?
Not sure if that works out cheaper in the long run, I've changed worn chains in the past and then the new one has started skipping because of worn chainrings.

I've got the tools to do it myself already, cheers stumpy01. Do agree it has saved me a lot of cash over the years!

We get free spannering, so mechanic checked it when I went in to get him to do a brake adjustment. Was surprised at the wear because my fixed checker didn't pick it up. A bit annoying that. Maybe making use of the Halfords PSA to get a KMC chain and a 105 cassette. Just need to figure out if I go 12-28 or man up and go 12-25 this time!

I thought the whole point of checking the chain was to replace it before it wore the cassette down as its cheaper to replace the chain rather than the whole drive chain?

I'd heard that 1.0mm was probably the trigger point, but some change the chain at 0.75mm to be on the safe side.

The only reason to change the whole drive chain is if the cassette is too worn for the replacement chain to link properly, so is that the case? and if so how have you done that with such low chain wear?

The point of replacing the chain at 0.75 is to avoid having to replace the chainrings and cassette every time.
If your cassette and chainrings need replacing and you are skint, why not just leave the current chain on, and save to replace all of them in a few months

5000km for a cassette should be nowhere near needing replacing on average, if it's on a reasonably maintained road bike and chains haven't been used for long beyond .75 wear.

Chain checkers are only a guide, but useful to keep tabs on wear rates. Check when new for a starting point, they're usually close to .5 then. I replace chains at .75 or soon after so that wheels with different cassettes on always mesh up ok, but one road bike is way beyond 1.0 now and all is running relatively smoothly. Cassette and rings are trashed, but it took a lot of miles to get that far.

Right then, I guess I should save this to just copy & paste in future:

Chain wear checkers (all except the top of the range Shimano one that's about £50) measure roller wear, roller wear is inconsequential (which funnily enough is why the top of the range Shimano one doesn't measure it!).

So, use a rule instead, and change chains that reach 12.0625” (12 & 1/16”) which is (0.5%), as per Jobst Brandt's & Sheldon Brown's advice.

It's a load of old cobblers.
I've never had a worn chain slip on worn sprockets or chainrings. Never.

It's a clever bit of marketing to make people think they are doing essential maintenance like a 'proper' cyclist. It's a great way of making people buy more chains, which in turn means people run newer chains on older cassettes, which in turn makes people buy more cassettes.

But hey, it's your money.

I've taken to using a chain checker. Irrespective of it's potential inaccuracy I have found that if I change a chain at .75% I can get one cassette reuse, come to .75% wear on the second chain and I get slipping so I reckon 1:2 cassette to chain, which I can cope with.

PS I have only a vague idea of my mileage, it'll be circa 2000 a year almost entirely offroad and in 'orrid winter gloop and reckon on a chain lasting about 6 months.

How many kms do you get out of:

- Chain?
- Cassette?

The chain is about 9 months old and about 5000km old. Does seem like a short time for it. The cassette is over 3 years old now!

My good road bike will be 4 years old in March.
I do anywhere from 600 to 300 miles a week. Original chain and cassette.

My old roadie had a groupset on that did a years road racing then 5 years as a winter trainer. Same chain, same cassette.

My full susser lasted 3 years with the original kit on.

Don't believe the hype.

Change your chain when you get a detectable mechanical problem with it instead of believing all that rubbish about chain checkers...

Exactly this.

My road bike is now 7 years old - original chain and cassette. Not planning on changing them any time soon. Must be upwards of 50,000 miles on them.

I do however appreciate that when I need to change on part i'll need to change the lot.

It's a load of old cobblers.
I've never had a worn chain slip on worn sprockets or chainrings. Never.

Just because YOU haven't doesn't mean it's cobblers my friend.
I see it several times a week at work. So you're wrong. 😛

crikey - Member

It's a load of old cobblers.
I've never had a worn chain slip on worn sprockets or chainrings. Never.

I don't change the chain or the rings or the sprockets until things start to malfunction, like above. Then they all get changed, well the big ring and granny last a couple of changes usually.

Dont bother with chain guages. Measure 12 inches. On a new chain this will be rivit centre to rivit centre over 12 inches. When the chain gets over 1/32 stretch on top of the 12 inches then change it. You will not have damaged your cassette or chainrings at this point. I think this is on Sheldon Browns web site if I remember correctly but he may say go to 1/8 of an inch which i feel is a little too far. Its the way I have been doing it for many years. I have had chain slip from worn chainrings in my younger inexperianced cycling days. Not fun in busy traffic.

crikey's chain never slips as it's so worn it has become elastic and can form itself to anything vaguely lumpy with ease..

run it all into the ground together is what i say

Change if you want to keep the same cassette for a while.

Keep if you intend to run both into the ground.

It's a clever bit of marketing to make people think they are doing essential maintenance like a 'proper' cyclist. It's a great way of making people buy more chains, which in turn means people run newer chains on older cassettes, which in turn makes people buy more cassettes.

😆

I don't trust those wheel things. It's all bloody marketing, I tell thee.