Replacement Chain

awol

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Sep 4, 2013
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At about 4000 miles I've decided to check my chain for wear using the measuring trick with a 12" rule and find my chain is about 1/2 the rivet dia longer which according to the info I can find suggests it need replacing. I was hoping to get at least 5000 miles(1 year) out of it.
My bike spec says I have an 8 speed KMC Z82 chain.
Any long distance cyclists recommend a harder wearing longer lasting chain? or do I have to replace with the same model. I have looked for replacements and find all sorts of makes/models and have no idea which one will fit.
Any tips on choosing a new one?
 
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flecc

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Oct 25, 2006
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The Z series KMC that you have are their standard chains, the X series are their very durable ones.

Here is the web page for those 8 speed X series chains, the top three are the toughest highest performance ones.
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mountainsport

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Feb 6, 2012
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The Z series KMC that you have are their standard chains, the X series are their very durable ones.

Here is the web page for those 8 speed X series chains, the top three are the toughest highest performance ones.
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Good new topic, but how does one know when a chain is stretched, worn or on it's way out. Would it start clacking when peddling ?

MS.
 

flecc

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By measurement as awol has posted is the usual way, though there are various recommendations on how to measure. Many just wait for failure or faulty running and replace chains and sprockets together as sets.
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awol

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Sep 4, 2013
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Good new topic, but how does one know when a chain is stretched, worn or on it's way out.
I followed the measuring instructions in this video.

Some chains say 'compatible HG' and some don't, I don't know what HG is but if I ended up with one of those would it do?
I will have a browse through that KMCchain website too and have a look at that X series chains.
 

trex

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HG stands for (Shimano) Hyperglide. Your crank is Shimano Acera, so HG.
Cannondale website suggests using KMC Z99 9-speed chain.
 

tillson

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May 29, 2008
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Good new topic, but how does one know when a chain is stretched, worn or on it's way out. Would it start clacking when peddling ?

MS.
When it starts to jump on the sprockets.

I just take the chain off the bike when it sounds a bit dry, clean, lubricate and re-fit. When teeth start to break off the rear sprocket due to wear, I replace the lot. I think I'm averaging about 8000 miles per chain and sprocket set.

I can't see the point in measuring for, "stretch" which is probably not stretch at all. More likely it's the sum total of small amounts of wear in each individual link.
 

JohnCade

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May 16, 2014
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Well yes. That's what chain 'stretch' is. But if you check the chain regularly and change it before the wear starts to damage the teeth then a cassette and chainring change won't be needed for a lot longer.

Chains are a lot cheaper and easier to change than cassettes and rings.
 

mike killay

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Feb 17, 2011
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My problem is the 11 tooth sprocket that hardly lasts 400 miles. The sprocket appears undamaged but the chain can jump it.
Did consider deliberately 'hooking' the teeth with a dremel.
 

flecc

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I think any sprocket under 13 teeth is problematic where wear is concerned Mike. Having said that, wear is a partnership issue between chain and sprocket, and a tougher chain can delay it. See my post in another thread about the tougher X chain in place of your recommended Z chain.
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amigafan2003

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Jul 12, 2011
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Any long distance cyclists recommend a harder wearing longer lasting chain?
4k miles is pretty good from a chain tbh, some of my off road bikes that get heavy use need new chains at 1k miles. KMC are good chains and reasonably priced - they are my preferred choice.

A chain is £15 but cassettes are £30 so it makes sense to change a chain before it can damage the sprockets. I normally get three chain changes per cassette - so a cassette lasts 3 times longer than a chain.
 

flecc

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Sadly the widespread adoption of derailleur gears killed the oilbath chaincase, and the similarly timed adoption of alloy frames assisted in that loss.

A chain and sprockets in a fully enclosed oilbath chaincase where the chain at the foot of the chainwheel is dipping into oil runs indefinitely for years, even decades, without any attention. That's not just due to the permanent perfect lubrication, it's also due to the total exclusion of dirt.
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For the poor guys that have crank-drives, they have to waste time measuring their chains and replacing them regularly. For those with hub-motors, it's just like my friend Tilson said: When it sounds a bit dry, oil it, and if, after oiling, it makes nasty graunching noises, it's time to replace it. Forget your measuring stick. I'm up to 500 miles on the chain that came with my worn out £5 bike. I still haven't oiled it yet. I think the measuring stick would be laughing at me.
 

flecc

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Dead right d8veh, chains and sprockets are little problem on hub motor bikes and the more powerful the hub motor, the longer they tend to last of course.

The experienced Dutch have largely killed off crank drives in their market and I think that will spread once the crank drive chain wear problem is more widely experienced over time.
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mike killay

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Dead right d8veh, chains and sprockets are little problem on hub motor bikes and the more powerful the hub motor, the longer they tend to last of course.

The experienced Dutch have largely killed off crank drives in their market and I think that will spread once the crank drive chain wear problem is more widely experienced over time.
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I tend to agree now that I also have a folder hub drive. Once manufacturers crack the hill climbing problem on hub motors, the crank drive days are over, that is unless sturdier chains and sprockets become available.
The appearance of the two speed hub motor, which I have not been able to try yet, could be the answer, because my little 20 inch wheel folder has a huge amount of push, but dies rapidly on hills if I cannot keep the speed over about 6 mph.
 

trex

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awol has hub bike, Tillson has crank drive and awol is looking for a new chain. Intuitively, I think we can agree that CDs wear chain, sprockets, rings faster - but the occasional posts do not prove that the difference is much.
I reckon the average number of worn chains, sprockets, rings per 1,000 miles is much less than 0.3 and largely predictable, compare that against the average number of broken spokes on the rear hub motor wheels about 1 to 3 and largely unpredictable, and the fact that replacing a broken spoke on a motor wheel is messier than replacing a chain, you can see the advantage of CDs from the low maintenance point of view.
Hub gears also help reducing wear because the chain does not need to jump.
 
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flecc

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But until this summer Tillson's bike had the lower powered 2008 Panasonic crank motor. It's today's much more powerful crank motors which have brought the problem of excessive wear, first coming to common notice with the Bosch unit where Bosch reduced the power a little and have since also separated the power levels on units for derailleur or hub gears.

That's coincided with the advent of more powerful hill climbing hub motors which could prove a game changer. I can't agree that broken spokes is commonplace on hub motor bikes, most never suffer a broken spoke.
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amigafan2003

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Jul 12, 2011
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For the poor guys that have crank-drives, they have to waste time measuring their chains and replacing them regularly. For those with hub-motors, it's just like my friend Tilson said: When it sounds a bit dry, oil it, and if, after oiling, it makes nasty graunching noises, it's time to replace it. Forget your measuring stick. I'm up to 500 miles on the chain that came with my worn out £5 bike. I still haven't oiled it yet. I think the measuring stick would be laughing at me.
Of course it does also depend on what kind of shift performance you're willing to accept. If I could live with the odd skip or slight hesitation in changing gear then my chains and sprockets would last 3x longer ;-)
 
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