Pouring 2 liquids into 1 container once a year is not a lot of trouble.

This is the heart of the matter. For 500 - 1000 miles it's almost immaterial what you use. The factory lube will last nearly that long.

Right. And again, we get back to the point that anything works fine, as long as you keep it on the chain somehow and you do a reasonable job of keeping the chain clean. So use what you consider to be reasonably priced and reasonably easy to use.

WD-40 is cited as a bad chain lube, because it dries too quickly and can even collect dust after it's dry. But you can even get it to work if you use it frequently enough. That's a worst case lubricant, and it isn't so bad. The very worst case is no lubricant.

Those who say that what lube you use doesn't matter if you change it often enough are way off the mark. If a lubricant (in any application, not only bike chains) is inadequate or inappropriate to the task it's used for it doesn't matter how diligent one in in using it.

In road use there is a marked different in expected chain life with the various lubes. I ran the Campagnolo service center when 10s first came out, and had to deal with chain life complaints on a regular basis. There were a few common traits of those who had the shortest chain life.

1- they lived or rode in hilly parts of the country,
2- they were clean chain lovers, and usually washed out the factory lubes
3- they usually used one of a short list (I won't name them here) of trendy lubes, and rarely one of a short list of better lubes.

Granted that I market a chain lube and am therefore biased, but I find it interesting that the same people that will spend hundreds if not thousands of dollars to squeeze out tiny incremental improvements in performance, won't spend $0.75 to properly maintain that equipment and get the performance they paid for. With chains costing $25.00 - $75.00, a small improvement in chain life pays for the lube many times over, not to mention the cassette.

FB, was cheap oil on either list?

I trust your opinions and observations. You've been around a long time and have greater sample sizes than most of us.

No, but that wasn't indicative of anything. People calling a service center trying to get a warranty replacement on their chain weren't likely to say they used homebrew, or cheap generic oil. As a matter of fact I don't remember one instance of any complainer using home brew. Also remember that the good products were conspicuous by absence, since I never heard form the folks who were getting good chain life, only those who weren't.

While for many bike chains are simple things that will work OK with anything, those who put out significant power - either riding fast (Chain tension is proportional to the square of speed), riding hills, on tandems or are simply bigger heavier riders - run their chains at higher tensions and the bearing load on the pins and rollers is above anything that would be acceptable in any other application. That calls for a lubricant with the proper chemistry for steel/steel friction, adequate film strength to perform under that load, and the staying power to continue to do that for at least until the next application, besides surviving rain, and spray off the front wheel.

I should also note that rarely among the complainers were folks who never lubed their chains, either because the factory lube was good enough, or because they wouldn't admit it. I also speak to the folks at Shimano who say folks who wash out the factory lube make up the majority of those complaining about chain problems.

Those who think oil is oil have never worked on high tech equipment and seen how tightly the lubes are specified. In some cases down to a single product from a specific source.

Wondering what a professional of any kind uses is a moot point. Professional of just about anything don't have to worry about the longevity of their equipment because they have access to new stuff all the time. A professional bicycle mechanic doesn't have to worry about make a chain last 5000 miles. He doesn't have to worry about making tires last 10,000 miles. In fact, he changes stuff on the bike on a regular basis so that everything looks showroom fresh. The bicycle is a rolling advertisement and the sponsor wants it to look good for publicity. Even the bikes aren't going to be more than a season old and, for elite level riders, less than that.

You and I, on the other hand, have to worry about this stuff. A better question would be what does an experienced bicyclist in your area use. Experience...with a dose of lubrication knowledge...goes a long way towards making you equipment last. For example, I live in a state where the average rainfall is 11" a year and 300+ days of sunshine a year. We have lots of grit and sand everywhere. (Grit and sand tend to be a very high percentage of quartz here which is harder than the steel.) A very wet lubricant, like most homebrews, is absolutely inappropriate for my area. Oil attracts grit like **** attracts flies and that grit just grinds the chains to iron fillings. If you are riding off-road around here, you specifically don't want oily lubricants. Wax based lubes work very well for me and don't attract a lot of chain destroying grit.

Areas where there is more rainfall have less grit...they still have some...but wax lubes aren't much good in the wet. An oilier lubricant makes sense in those locales. Wax can be used but you are going to apply it much more often than I have to.

FB, I realize that a ton of R&D have gone into oil and continues to. I would not say oil is oil. My impression is that the average rider doesn't have special needs for special lubricant. Please feel free to disagree. In fact, I welcome your opinion on that.

The fact that tension is proportional to the square of speed is interesting. I'm sure there's a relationship to power, too. In fact, my guess is that that is the real relationship, and it secondary one is that power is a function of speed and therefore to tension. So take Rider A, Rider B, Rider C, and Rider D at the same weight and speed (and air drag). Rider A adds some speed, and Rider B adds weight to his bike. Rider A is now applying more power and thereby tension to his chain. Rider B is now applying more power and thereby tension to his chain. They are both applying more power than Rider C is. Then Rider D takes a different route, heads uphill, while the others stay on flat ground. He maintains his speed. He is also adding power (and tension) and is applying more power than Rider C.

Would you agree?

Sorry, bike chains (and every bearing on a bicycle) are essentially very low speed, very low load no heat application which any conventional lube will handle with no problem, so oils is oils.

As you mention, whats important is how you use the lube. Wipe the chain down every time you ride and lubing sparingly every other ride (and never cleaning with solvent) and your chain will last a long time with any oil.

The rider doesn't have special needs, but the really incredibly crappy chains do. All bike chains designed to fit 8, 9, 10 or 11 speed spockets are incredibly crappy. Lots of work goes into making them less crappy, but they're inherently crappy; they don't have enouh bearing surface for the load they carry, and the lubrication is pretty awful.

The power to tension equation is a bit tricky, because power is a measure of work (force X distance) over time. For example imagine two riders of equal weight climbing a steep hill in the same gear but at different speeds. Discounting the effects of wind drag both are applying the same pedal pressure and therefore have the same chain tension, but the faster rider is exerting more power because he's moving a more distance in less time.

Wind drag is more complicated because the wind drag is proportional to the square of the wind speed, so the motive force and resulting chain tension is likewise related to the square of the speed. The power requirement ( and chain tension) is proportional to the drag coefficient, so at the same speed the bigger less arrodynamic rider would be working harder. But for two similar riders at with the same drag coefficient, greater power implies greater wind speed, so the power requirement is proportional to the cube of the wind speed.

This is why the peloton is such a monster in the flats where it's aerodynamic advantage grows with speed, and much less of a factor in the climbs where most of the work is against gravity, and the wind factor diminishes.

Here's a link to more info on the relationship of wind and power, from the opposite perspective.

A popular mis-conception. Low speed definitely, which helps but low load definitely not, which partially accounts for short bearing life that would be totally unacceptable in any other commercial application.

Consider the chain's bearing load. A 150# rider stands on the pedals climbing a hill. Since the chainring is roughly half the radius of the crank the 2:1 leverage means 300#s chain tension. Now consider the working surface area, approximately 1/8" long and on a worn chain about 1/16" wide at most or roughly 1/128 sq.inch. For the sake of easy math lets call it 1/100 sq.inch. That means the load is 30,000psi (or more). Compare that to standard industrial applications where bearing loads are kept at between 500 and 2,500psi.

Bring any mechanical engineer knowledgeable about chain drives the specs for bicycle loads and speeds (without saying it's for a bike) and he'll recommend a chain wider than a motorcycle chain.

So, I'm sorry but oil does make a difference, albeit less so in Kansas than in Colorado.

No! A bike is a fairly simple mechanism that is light loaded. How many newton-meters does a cyclist exert? About 750N (~75kg weight) * crank length (0.1725m)=129Nm
The chainring has 39T (for example), that is z*modulus=Diameter, modulus of tooth for a bike is ~4.05mm => diameter of chainring is 0.157m, radius is 0.0635m
The tangential force at that point is: 129/0.0635=2031N (around 200kg)

A chain that holds 200kg is not a fuss. A comparation with motorcycle chain or industrial chain is not possible.

*this is only an empirical calculus, and not an actual engineering, If I want I can make a fairly accurate calculus of engineering but that require time and effort that is unnecessary in this context, such a thing I'll do if I'll be working in a chain factory.

And FBinNY, a chain is not calculated at psi load on the surface, and the area of contact is on multiple teeth, it's not that simple, such a calculus is made to evaluate the stress on a tooth of the sprocket, not on the chain. Of course, a fairly documented project should contain verification of bending the pins, and "scissoring" the pins, elongating the plates, etc.
An overall information about a chain as a whole is it's maximum tension before breaking, but this is also hard, the chain does not tear the plates or the pins, it only uncouples itself.

I roughly estimated 300#s so we basically agree so far. Statically loaded 300#s is no problem, but we're talking not of strength but of wear which is different. Realistically a decent rider can expect about 3,000 miles life out of his chain, some more others less. If he's a decent rider that's 200 hours or less (at 15mph). In that time he'll have worn 0.025" (1/16" in 12 stretch) off the pins and journals (combined).

So two questions, in how many applications would 200hours max service life be acceptable? and in how many plain bearing applications would .001" wear per 100 hours be acceptable?

We can debate this forever, but chain life varies tremendously rider to rider, based on a variety of factors, geography, power and lube being just three. If not being strained to the max we'd expect a much narrow spectrum.

Simple fact, yes bikes are simple, but performance bikes are severely underbuilt, because who in his right mind would want to compete on anything that's overbuilt. If anyone ever finds an unused reserve of strength anywhere on a bike it's immediately fixed.

Actually your calculation gives a higher tensil load than FBinNY's. He estimated about 300 lbf and yours is about 440 lbf.

Why not? Bicycle chains are chosen to be flexible to allow sideways bending for shifting, for light weight and to be narrow enough to fit between the adjacent cogs. No industrial designer would ever use such a small, narrow chain for such high loads if they expected typical industrial service life.

The "area of contact" pressure calculation is based on the tension in the upper run of the chain where the load is the greatest. The number of links supported by the chainring and cog teeth isn't germain.

Note to the OP: See what your seemingly innocent question started? :)

OK, now we're talking. This is the sort of stuff I want to see here. First, we have some numbers, and they are not from measurements but they are honest estimates. Good enough for me. Second, we have to decide what the important questions are.

Let's clarify. We're talking about what causes wear and how much wear it causes. Tension causes wear. Tension plus contaminants together cause more wear.

We have added sprockets to our cassettes, requiring narrower chains. Narrower chains have smaller bearing surfaces, which increases tension.

When was the last time you replaced a 1/8" wide chain because of wear? Uh, I can't remember ever doing it.

I don't know how many miles I put on my bikes. I ride more than most people I know but a lot less than a many people on bikeforums. I also have about five bikes I call my own. My oldest bikes have chains that are over 20 years old. They are Sedisport chains, and they are on six-speed freewheels. I can't say if I'm getting more wear (hours or miles) out of my chains than other people.

I do know that I'm not eager to convert my bikes to 9- or 10- or 11-speed cassettes. I have one bike with a 9-speed cassette and a new Shimano 9-speed chain. I've only been riding it for a year.

Some people don't give a hoot when they have to replace a chain due to wear. Some want their chains to last.

I'm disappointed that so much emphasis has been placed on adding gears. They are nice to have, for sure. But I could live without them, and I don't like the idea that chain longevity is sacrificed for the extra gears. I've also seen several reports of 9- and 10-speed chains breaking while riding. Have we sacrificed chain reliability? That's nuts. I've never snapped a chain, and I hope I never do.

Tom, watch your choice of words, narrowing the chains doesn't increase tension, which is determined by pedal pressure and sprocket size, it increases stress within thinner plates (tension/crossectional area) and bearing pressure (Tension/bearing contact area).

In any case, any breakage of narrower chains probably wasn't the result of lowered strength, but probably because aggressive shifting pushed outer plates beyond the zero overhang pins. I've also seen some chains because of stress fractures at the pin holes, which I chalk up to either heat-treating or manufacturing tolerance errors.

For those interested, I'm considering collecting data from riders of chain life, and a bunch of variables, such as brand, width, lube, rider weight, terrain, etc. To be of value the project would take a decent amount of time and would need a large sampling of riders, but conceivably with a large enough database, some patterns would show out and conclusions could be drawn. If someone knew how to set up a survey here, I'd love to know how many would be interested in participating.

Frank, I forgot about the fact that the rollers, pins, whatever they're called are NOT narrower. Only the sideplates are narrower, and that's how they fit on narrower cassettes. Correct?

So is it accurate to say that the new chains are more prone to breaking? And if the rollers are not narrower, why are the narrower chains wearing faster?

I will do some research for you on how to conduct a proper online survey. Collecting the data is the most important thing. You need a big sample size to make an accurate conclusion. It might motivate me to keep track of my mileage on each chain and how often I lubricate it.

My father was Demetrescu from Petesti.

Just wipe off the excess and dust which isn't a problem will have less to stick to. The wear particles from inside the chain that color it black are from the hardened pins and inner plates wearing and contribute to the wear.

Traian Demetrescu?

http://upload.wikimedia.org/wikipedi...m_ILR_562.jpeg

The inside width is marginally narrower but The width of the bushing part of the plate is narrower on the 10s chains I've looked at than on some of my older 9 and 8s chains, by more than the change in inside width. I suspect that when they thinned the plates, they were no longer able to deep draw as much "bushing" width as they had in the past. Either that or there was an election to narrow it for other reasons (I don't think it was to sell more chains). It's also possible that there were changes in material and heat-treat of the thinner plates to prevent fracturing.

I suspect that the shorter life of 10s vs 9s chains probably has more to do with changes in chain lube preferences and practices and the use of 11t cassettes than changes in the chains themselves.

That's one of the reasons I want to accumulate a large enough sample of chain life data. If it's big enough and the data is collated out properly it might help draw better conclusions than the anecdotal data does.

You meant Pitesti ;) . Demetrescu is a common name in Romania.

For chainwear best it would be to trace a Wohler graph (which consists of points of break, in ordinate it's the force (fixed at a value of choice, an alternating or pulsating force up to a value), and in the abscissa it's the number of cycles needed to break (or elongate 1% in this case for example), but such a graph is usually well guarded, because it's hard to controll all variables, and also involves breaking a chain at every point on the graph, also that number of cycles is hard to reach and is necessary to run days, weeks, months, etc.. - On such a graph you could tell the wear rate by condition of use, also life expectancy, and for the manufacturer can observe what is the lifetime of the chain at normal use and see if the chain was too poor and breaks/wears very fast or it wears very slow (and it will probably promote it in upper class and sell it for extra $)
Wohler graphs are basically a dependency of load value, and fatigue limit for variable loads.

It's sad that many things in bicycle industry is made on other considerations rather then mechanical/price ones, because some aspects are not made by engineers, or are made in their coffee/toilet break. Like hard anodized aluminum on mavic MA40 rims, they crack at joints, Aluminum chainrings (they wear out a lot faster than steel), titanium cogs (it has low superficial durity, it wear out quick, even if it is strong for bending, twisting, its scratched very easy), a lot of mixed materials especially aluminum bolts and steel threads (it will lock there like forever by galvanic action), and a lot of other little things.

Let's factor out breakage and concentrate on wear. They are two different things. I'm willing to believe that breakage is sufficiently rare that it's not a concern.

To the OP.....I have no idea.....but I would imagine your answer is as divers as as the posts on your thread.