How long should a chain last?

[TigerFish]

I have slightly over 2,000 mi, 3,200 km, on my current chain. I ride with a two ring crankset and ten gear cassette. I avoid cross chaining. I did a significant tune-up and cleaning yesterday. My chain looks fine. Is there any general rule for how long a chain should last?

 

[Black Dog]

There are so many factors that effect the life span of a chain. You need to get a chain wear measuring tool. They are cheap and will tell you when the chain is stretched to the point of needing replacement. Just measure periodically and when you are close to the maximum length then replace. This way you will never change a chain too early or too late.

http://www.parktool.com/products/detail.asp?cat=5&item=CC-3

 

[The Mann]

You can also use a ruler if you don't have access to a special tool. A standard half inch spacing chain should measure 12 inches over 24 links.

 

[dsut4392]

You can also use a ruler if you don't have access to a special tool. A standard half inch spacing chain should measure 12 inches over 24 links.

If you're doing this, you need to remember that the chain itself doesn't "stretch", i.e. you won't see any change in length measured between the centres of the pins.

What cyclists call chain stretch is actually wear primarily between the inside of the rollers and the pins (and to a small extent on the surface of the rollers), and I personally find measuring this with a ruler to be fiddly and inaccurate as you have to spread the rollers at each end of your measurement apart. Using a "%" stretch measurement is also deceptive, since it's usually calculated over those 12 inches, yet the absolute 'stretch' between any two links should be approximately the same. Because the centres of the pins stay at the same distance apart, the wear or stretch over multiple links isn't cumulative. So a 1% stretch over 12 inches could just as well be measured as 4% over 3 inches.

So what should you do? Buy the chain measuring tool for about $10 and use it regularly.

 

[brianf7]

Your chain should be replaced every 6000 killometers .
new chains dont stretch as much as the old ones but they are still wearing out.
when they wear they eat into the sprockets and chainrings so if you keep riding untill it breaks you will need to replace all running gear (expencive)

As it wears it becomes weak. I have seen chains that hane no stretch in them but still snapped and caused a big accident in a race something that cost a lot more than $50 for a new chain. try 6 weeks off work with broken bones
6000 get rid of it and all will run smooth. I have seen chains break too many times.
Every squar inch of skin is worth $1,000

 

[Black Dog]

Your chain should be replaced every 6000 killometers .
new chains dont stretch as much as the old ones but they are still wearing out.
when they wear they eat into the sprockets and chainrings so if you keep riding untill it breaks you will need to replace all running gear (expencive)

As it wears it becomes weak. I have seen chains that hane no stretch in them but still snapped and caused a big accident in a race something that cost a lot more than $50 for a new chain. try 6 weeks off work with broken bones
6000 get rid of it and all will run smooth. I have seen chains break too many times.
Every squar inch of skin is worth $1,000

Why 6000km? That is simply arbitrary and not based on sound reasoning. Chains can wear out long before 6000km or long after depending on the chain and the many factors that effect wear. A properly designed, installed, and maintained chain will be very very unlikely to break. It does happen but very rarely, and age is often not a causal factor; it is usually a defect in materials or manufacture.

 

[AnythingButKestrel]

Where do I buy these guaranteed 6000 km chains and how much are they?

Whatchu got for miracle mile bottom brackets? I just blew through my first one in 400 miles. How much for a 6000km one of those?

 

[on3m@n@rmy]

All good advice. I'd just add that at around 2,000 miles your chain is probably pretty close needing a replacement. However, as one guy said there are lots of factors. Like, I've got about 3,000 on my current chain and it's still good - with very little crossover just like yours.

 

[locker]

if you degrease your chain every week and the re lube it'll last alot longer than the 3000km manufactures suggest

 

[Master50]

Where do I buy these guaranteed 6000 km chains and how much are they?

Whatchu got for miracle mile bottom brackets? I just blew through my first one in 400 miles. How much for a 6000km one of those?

When you replace that BB make sure the BB shell has been faced. Unless you were riding in water up to the bb it should not die that fast.

 

[analo69]

Go back to the old square taper models. The one I've got from campagnolo is supposedly made to last 60.000 km. Impressive if that is true.

 

[BroDeal]

Go back to the old square taper models. The one I've got from campagnolo is supposedly made to last 60.000 km. Impressive if that is true.

Maybe it's just me--it probably is--but I have never been able to get a consistent reading with a chain tool or a ruler. So I just pick a distance between 3000 and 4000 kilometers, and replace the chain when I hit the target.

 

[Polyarmour]

I got 20,000km out of my last chain before it started giving me problems. I think a lot of the advice surrounding chain replacement is based on having you buy more chains.

 

[Megalodon]

Most chain tools don't work:

http://pardo.net/bike/pic/fail-004/000.html

I bought a Park and Rohloff years ago and regret buying them. The Rohloff tells me that brand new Shimano chains are almost 0.75% worn.

I had trouble measuring chains the proper way using a ruler so I bought the Shimano TL-CN41 tool, the only tool currently available that actually works.

 

[hiero2]

Some of the other posters here have lost me - I don't get how anyone could find measuring a chain with a ruler anything other than simple. I've always measured mine every time I clean and lube them. When they are off the bike, it is dead simple. You lay the chain on a flat surface, next to a ruler. Pull it out so it is stretched out - you don't need to keep it in tension or anything, just pull on end while holding the other. Since it's lying flat, it doesn't go anywhere when you let go. When twelve links measure (pin center to pin center) 12 1/4 inches, it's time for the chain to go.

I like the page megalodon linked to: it says it all, and well.
http://pardo.net/bike/pic/fail-004/000.html

When I was racing and riding 5-10,000 miles per year, I'd get 1-2,000 miles out of a wet lubed chain, and 3+ thousand miles out of a plain old wax soak. I might have gotten 5 or 6K miles out of some of the waxed chains, but I quit paying attention after I settled on wax as my preferred lube. Since I measured all my chains from when they were new, wear was obvious.

I have heard that oil-bath chains will get nearly unlimited mileage - but I don't think anybody sells bicycles like that any more. Even when I was racing, I thought they were something very old-fashioned that you only saw in rural Ireland or Wales (or maybe other parts of the UK - those are the only rural sections I saw). Don't know the truth of that.

 

[D Avoid]

KMC DX10SC , got mangled a few times, had to shorten it after I closed the connector improperly, got it mangled against the frame last week, 5000 miles I'd say, at least 4, 17 months, £16 to buy, raced regularly. It was cleaned regularly, always after rain. I have a new one, spare, in the bag, 12 links measures excatly 12 and a quarter. no one should use inches, a mill is a mill, bits of inches are a very sloppy method. It also gets an awful kicking as I like to put the boot down in a big old gear.

Some old boffin told me last month, that after 3 months the performance of the chain is heavily impaired, he explained in his mad old man method, but it all came out as excess oil. Very messy , had to brush his teeth, false, with white spirits and wire wool, 000 grade.

 

[D Avoid]

Ok , so it's twelve(305 mm) centre to centre.There is some atrocious maths on here, .75 % worn, that implies there is 99.25 to go. Don't assume that because you understand what you write that it is true for the reader. The assumption being that you meant 75 % worn, making people decide between assuming the inobvious, but only avaiable punkclusion, and joining a monastery is not fair.


Polyarmour "I got 20,000km out of my last chain before it started giving me problems. I think a lot of the advice surrounding chain replacement is based on having you buy more chains."


I'd go with that, dishonesty is rampant in any industry where the knowledge base is hugely weighed to the advantage of extremely secretive manufacturers
and morally deficient shop, I've met them, not often, but once is to many.


Square taper?

Oil bath chain?

 

[hiero2]

. . . Don't assume that because you understand what you write that it is true for the reader. . . .

Always good advice, equally true for the spoken word. I spent some time in Russia, working, and received quite an education on all the assumptions that we English speakers make in day-to-day conversation! Amazing!

. . .Oil bath chain?

Ya, oil bath for a chain - I did a quick google, and came up with this example

The bike was fitted with the little oil bath in the chain case which means that the chain was always running in oil for lubrication,

from
http://www.bicyclehistory.com.au/bicycle%20related%20articles.htm

Apparently, some versions of an oil bath case are still manufactured as aftermarket add-ons, as is evidenced in this link:
http://www.phred.org/~alex/bikes/chaincase.html

AND, there is an image at the bottom of this page:
http://www.m-gineering.nl/oldtechg.htm

 

[TigerFish]

Found a tool & replaced the chain

I bought a new chain and found the old style stamped metal chain measure device similar to Park’s. Park has a newer better-looking tool but it is roughly $20.00 US. Being cheap I kept looking until I finally found the old style stamped metal measure device on sale for $6.99. The tool I bought is by Spin Doctor

I bought a new SRAM chain under the assumption that it would be needed at some point if not now.

The tool indicated the chain was way beyond the point of replacement. The tool fit very loose on the 1% measurement. I really can't say how well the toll measures incremental wear. It is very good at indicating extreme wear. I laid the chains out side by side. It was obvious the chains not only wear but they do also stretch. When I put the new chain on the improvement in performance was exceptional.

I was surprised how rapidly the chain went down hill once it reached the point of wear. Over a two week period the chain increased significantly in noise. When I originally asked the question the chain was making a little noise in two gears. By the time I got it replaced the noise was almost embarrassing in four gears.

Thanks for all the help, learning keeps me interested.

 

[Boeing]

Its a good question. And my experience is it depends.

Chain stretch is something worth measuring every 1200 miles if not before. I replace chains more often because a stretched out chain, while still function-able, will wear cogs faster than I want to replace my cassette. for me anyway might be different for others

 

[Polish]

I have slightly over 2,000 mi, 3,200 km, on my current chain. I ride with a two ring crankset and ten gear cassette. I avoid cross chaining. I did a significant tune-up and cleaning yesterday. My chain looks fine. Is there any general rule for how long a chain should last?

As a general rule, if you want to avoid excessive wear on cassette and chainrings - replace every 3000 - 5000 kms.

If you are fat, powerful, or ride on grungy drivetrains you will need to change more often than 98 pound weaklings who clean their chain before and after every ride.

It is also important to realize modern narrow chains wear/weaken laterally side to side in addition to stretching lengthwise. Chain stretch tools do not measure this side to side wear. Many chain failures are lateral failures.

 

[Fenceline]

Replace the chain as often as you feel you must.
It is true that worn chains will wear sprockets.
Also worn sprockets will shorten the life of a new chain.
My advice is to run 2 chains on each set of sprockets and then replace the entire drive train.
As an experiment I ran an eight speed MTB drive train for approx. 30,000km without replacing or cleaning any components, merely using copious amounts of oil to regularly lubricate.
The result was that the entire system became filthy.
At about 5,000kms the chain was noticibly worn but did not affect function.
At about 10,000kms the chain was badly worn, did not affect function, but became noisy and sprocket teeth showed signs of wear.
At about 20,000kms the chain was severly worn, function was affected, and sprocket teeth showed of obvious signs of wear (hooking).
At about 30,000kms the chain was severly worn, some of the rollers broke and fell off the chain, and sprocket teeth were worn right through and beginning to shorten. At that point the chain was jumping under power and becoming a danger.
I felt I had extracted all of the life from those components at that point.

 

[D Avoid]

Always good advice, equally true for the spoken word. I spent some time in Russia, working, and received quite an education on all the assumptions that we English speakers make in day-to-day conversation! Amazing!



Ya, oil bath for a chain - I did a quick google, and came up with this example

from
http://www.bicyclehistory.com.au/bicycle%20related%20articles.htm

Apparently, some versions of an oil bath case are still manufactured as aftermarket add-ons, as is evidenced in this link:
http://www.phred.org/~alex/bikes/chaincase.html

AND, there is an image at the bottom of this page:
http://www.m-gineering.nl/oldtechg.htm

Great links there, I love steam engines as well.

 

[oncehadhair]

about 4000 ks or 1% wear - wear gauges are cheap and a great way of checking.

 

[hiero2]

. . .
I felt I had extracted all of the life from those components at that point.

hehehehehe - yup, you sure had!