Chain wear

[Nigelnaturist]

Mod note:

This disagreement about WD40 is not helping the original poster. Back on topic from here please.

Sorry.

 

[MarkF]

You still using the same tyres ?

Yep, 35mm M+'s, I specified them with the bike, rear on it's knees now, front a little left.

I will post a thread in the next week or so showing how the bike has faired in 10 years and what has been spent on it, it'll be illuminating for some. I reckon the chain could go for another 1-2k miles.

 

[gbb]

But mine has lasted 10000 miles at least, wouldn't be surprised if it was 2 or 3k more. On only £ shop oil & WD 40, something doesn't add up.

BTW The Discovery 501 has only had brake blocks in consumables in 10 years of use, it's still on the entire original drive chain, wheels and M+ tyres!

You're not the only one...there is another forum member who gets really good mileage, although IIRC he uses only WD. We can only speak as we find, it doesn't work for me, it does for you. I'd love to know why because it did give me the cleanest chain I ever had.

 

[Blue Hills]

KMC Z7. I went for a SRAM PC870, which will be going on this afternoon.

If you want to save money in future it is my understanding that 850 is to all intents and purposes the same chain, but with just a plating difference. Plating won't have any real effect on resistance to rust unless you are really lax on basic chain care. I understand also though that the 830 is different/poorer so best avoided.

 

[Ihatehills]

@rivers, I seem to go through a chain every 1000 miles or so, the first one lasted less I'm guessing that my lubrication practices are not sufficient. I do ride on dusty tracks in fact I live at the bottom of a mile long farm track and my chain gets really grotty in next to no time, I've tried mickling but probably not regularly enough and my normal approach of just throwing some more lube on top of the thick black gunge isn't cutting it.

 

[mjr]

I do ride on dusty tracks in fact I live at the bottom of a mile long farm track and my chain gets really grotty in next to no time,

Here are three things that each improved my chain condition a lot, in ease of fitting:

• Proper front mudflap, wider than the already-full mudguard and down to a kerb-height off the floor (I think I'm using a Bibia Tour at the moment)
• Chain guard that shields the front of the chainring (currently using an Axa GSR, but I think a Raleigh ACD215 would do and would fit more bikes more easily)
• Hub gears instead of derailleur so that the back of the chain run isn't so low down near the dirt or running twisted ever

 

[Tojo]

I am curious to know what you were trying to achieve with this post.

Sorry just back, I wasn't trying to achieve anything, I did not mean to be derogatory, I thought you would be the one on here to give advice, and I thought you might have seen it as a joke, but not as it happens, my fault I worded it wrong, no offence meant, my sense of humour is not the same as yours. apologies...

 

[si_c]

I ride usually 5-7 days a week, through all weathers, my last chain lasted ~3200 miles through winter last year, was properly worn when I replaced it. Current one has just under ~1000miles on it, not worn at all, both KMC X10 chains. Thinking I probably should put some lube on it soon though.

To the OP, sounds like that chain gave up a bit early, no real idea why that might be other than just a badly made chain. Keep an eye on the next one, use your chain checker, replace when at ~.75. If you leave it longer you risk needing to replace cassette too.

 

[uclown2002]

11 sp Ultegra chain with 3900 miles still showing less than 0.5% worn.
To be fair, only ridden in good weather conditions.
Looks good for another 500 at least.

 

[Yellow Saddle]

11 sp Ultegra chain with 3900 miles still showing less than 0.5% worn.
To be fair, only ridden in good weather conditions.
Looks good for another 500 at least.

That's some very high mileage for a chain. I would doubt the chain checker and measure it using a ruler. Chain checkers give a different reading when the chain is clean and when it is dirty and the difference is enough to push it over the limit when you're getting close to the limit. The ruler method on the other hand, always gives the same reading even if the chain is dirty.

 

[Ajax Bay]

If you have no issues in changing up and down etc just carry on and keep it.

I do not think that this is good advice. The chain will change up and down 'happily' even when worn beyond the point at which it is prudent to change it (to avoid disproportionately wearing out the cassette as well).

I would doubt the chain checker and measure it using a ruler. Chain checkers give a different reading when the chain is clean and when it is dirty and the difference is enough to push it over the limit when you're getting close to the limit. The ruler method on the other hand, always gives the same reading even if the chain is dirty.

To elaborate on the 'ruler method' ^^, last year@Yellow Saddle commented one of my posts in which I recommended "counting 10 double links, measuring them accurately (in tension, along the line of the chain which you've aberationally put large to large)" and seeing if it's elongated by more than 0.75% (circa 1/13"): implying that the chain should be changed without undue delay.

Mathematically of course, your argument is sound. But, measurement with a crude instrument for small discrepancies is not as simply as extrapolating for a new length. The measuring error when working with a chain in-situ is large, there is a parallax error and the notion that your error is at least half of your smallest calibration. In a worst-case scenario the measuring error will therefore be larger than the elongation you're looking for. When you thus mathematically intrapolate when measuring a short section of chain, you increase the percentage error enormously. That's why the most accurate measurement is taken over the longest piece of chain possible. On a bicycle this section is available at the bottom run of the chain, when the front sprocket is large and the rear one small. This gives you an approximate 14 inch section. A good tool will take up all the available space. This is another reason why these short little commercially-available tools are inaccurate.

Personally I use the mm side of the 18" steel rule (which reduces the length of the smallest calibration to 0.5mm). 10 double links when new should measure 254mm and when the length gets to 255.9mm it's time to change. Given that most people will not take the chain off to measure it, measuring 14" is better than measuring 10" (ie along the bottom run rather than the top run, with the benefit that the bottom run is kept in tension by the RD spring): the relevant lengths are: 355.6mm and 100.75% of that is 358.3mm.

 

[Yellow Saddle]

[QUOTE 4474823, member: 9609"]for my long term lube tests I measured the whole length of the chain, it is the only way to observe the minute changes that take place every 100 mile. I permanently attached a ruler to a board in the garage and measured all 54 links.
In the example below I measure this old chain at 1381.3mm 0.7% wear. (i like to bin them off before this point)
Roughly I will observe about 1mm of wear per 100 miles

On aspect of chain wear that no one mentions is how much ascent has been done. I haven't got any exact figures yet, but certainly chain wear on a flat ride could be half that of on a hilly ride

[/QUOTE]


You are bloody OCD but you know that, don't you?

Keep it up, I love it.

As for ascent/descent, your observation is correct, that would be a difference but to factor that in to any long term test is impossible.

There are several variables wrt chain wear if we take mileage as a invariable.
a) sprocket size (smaller causes more wear)
b) tension (related to gear pushing and ascent/descent)
c)Hygiene i.e. what type of contaminants does your ride splash onto your chain.

It is impossible to factor this in with some sort of formula. Your only chance is to do this experiment in a controlled environment. I'd rather drink beer in a controlled environment.

As for your measuring jig - what do you consider to be 100% wear? You mention 75%.

 

[Nigelnaturist]

[QUOTE 4474925, member: 9609"]
So all these cyclists who have exceptionally long chain life and claim their maintenance routine is the best, may indeed just have very weak legs. [/QUOTE]

I suspected as much would explain it.

 

[Erudin]

I use a Park CC-3.2 chain checker and replace chains on the road and audax bike soon after the gauge shows .5% wear (entire chain around 7mm longer than when new).

Changed the KMC 9.73 chain on my audax bike today, it had worn .5% after just 809 miles (according to Strava's My Gear Component section).

The Connex Wipperman 904 9 Speed Chain on my road bike is doing better after 2000 miles than the Shimano HG93 it replaced. It's been getting a thorough clean, degrease and lube about every 200 miles.



http://www.bikeradar.com/road/gear/article/bicycle-chain-wear-explained-46015/