OK, try this; stand on a bathroom scale. Holding onto a handrail or other secure handle, pull up. How much more than your body weight does the scale read? Probably about 10%. If you're really strong, MAAAYBE 15-20%. Try it, and let us know what you find.

I'm curious about this chain stretch thing. Theoretically, if the chain is longer, then the amount of wear on the pivots/pins will be multiplied by the greater number of links, creating more stretch for a longer chain for the same amount of actual wear in each link. Is this accurate? It's only a thought.

Still, the amount of "stretch" to measure would still be the same as for a DF bike chain, shouldn't it?

Chain elongation is measured over a certain length of chain, but what you're really looking for is the % of elongation. Of course if you double the length that you're measuring, and if the % remains constant, then the total elongation you measure is doubled too.

I'll try the experiment, DD. Although it may take a bit to set up, maybe using a gate to the paddock. I know that I can start a road bike in a arirly high gear, i.e. 52/14, and with some effort and hard pushing get up to speed. In fact, that's how I've broken chains. Doing the same on my recumbent takes much longer, implying that I'm NOT pushing as hard.

Eh?

If that were an accurate test and estimate, it would indicate that a person could only lift 15-20% of their body weight if they were "really strong." Think about that for a moment. You'd be in sad shape if you could not lift at least 50% of your body weight, or in other words apply your body weight + 50% in pounds of force to a scale. I foolishly tried your experiment, at a hair over 200lbs., and exceeded the 300 lb. capacity of my digital scale. I could have applied more pressure, but the vanity was making funny noises.

I'm not saying that on a bicycle you can apply that much force to a pedal, but that's why we have gears.

Chain wear though...a chain should last longer on a recumbent if everything else is equal. The chain parts do encounter the gears less frequently, and stretching forces across the top of the chain line are applied over a longer stretch, or more links, at any given time.

I would like to add when i'm rushing for the lights or attempting to climb a steep hill. I pull very hard with the other leg on the up stroke! Not a clue what extra this accounts for but it is a great help being clipped in.

When my Park chain wear and my steel rule says to do so. YMMV

I know that I haven't replaced the chain for the third time on my second trike, a Greenspeed GTO with 27,000 miles on it. It is also on the original chainring but that's mostly because it is a 65 tooth Schlumpf chainring costing $135 to replace. I did replace the rear cassette and the Shimano 105 RD when I replaced the chain the first time. It pays to lubricate the chain frequently. Much cheaper than replacing the entire chain which takes over 2+1/2 standard 112 link chains. I doubt it would have lasted that long if I put excessive force on the chain.

Uh-oh! Time to load the shotgun; the zombies are out!

Yeah, but I've wondered about this for a long time. My chain probably has 6500-7000 miles to it. I check it with the Park thingy and it seems to be fine. I'm not compulsive in my bike maintenance but I don't neglect it, either. It just takes a long time to properly clean and lube a bent chain.

Those products moved in the website. Here's the Park Tool Chain Wear Indicator, Park Item CC-3.2. Search for it at Park Tool Co. » Park Tool Co., which explains it.
http://www.parktool.com/uploads/thum...c4_430x390.jpg

Well... as long as we're resurrecting the thread...

Chain wear mostly occurs when a link pivots under load. So wear happens going onto the chainring and coming off the cassette gear, and possibly at the power idler, if one exists. Some wear happens at the other bends, but it's minimal. The chainring and cassette are the same for both styles of bike; but a recumbent chain being longer will only put a given link through the wear areas 1/3 as often. Even counting the power idler, a recumbent chain should still only wear half as fast as an upright chain.

I was on a 25 mile ride yesterday with three other riders. None of us had ridden them less than 4,000 miles. Two were on DF bikes and one on an HP Velotechnic Street Machine, I on my CT700. I asked them how many times they had replaced chains. The answer was zero for everybody. One DF rider has 14,000 miles on his DF bike. I know the guy on the HP Velo has thousands of miles on his. Maybe it is just a matter of riding in an area where it rarely rains. The desert does tend to be dusty, particularly when the wind is in the mid 20 mph range as it was yesterday.

There's a tool to check for chain wear....always change out the rear sprokets with a new chain

My experience (46 years of cycling and DYI on my own bikes) tells me that you should never put a new chain on a old cassette. It just grinds the s*** out of both. I usually replace the chain when the cassette is shot. The crankset gets replaced every other time, but if a guy was Rockefeller, you'd just change all the running gear out every couple years. I ride about 2000 miles a year.

Congrats on your first BF post! And congrats on resurrecting an eight-years-sleeping thread!
Were you perhaps trying to post to a current clipless pedal thread?

I don't keep close track of chain mileage but have recently started checking with a yardstick......
Don't usually replace cassette with every chain change but I'm always alert for chain skipping after a change.

Every forum I've participated in considers responding to an old thread to be bad form.. but I've never gotten a good reason why other than some weird social convention. So what's your take on it?

It depends on the specifics. If someone resurrects a long-dead thread to provide closure, that's great. But it's kind of senseless to pull up an 8-year-dead thread to say "me too;" or in this case to make a reply that should have gone in another thread anyway.

Of course, the flip-side to the argument against zombie threads is that when someone asks a question that was posed 8 years ago, the old-timers will invariably point to the dead thread and say, "you should have posted here." Which goes to prove, sometimes you just can't win.

Using Mobil 1 to lube the chain, and wiping it down after every ride, and completely cleaning it in kerosene once a year, I got 8000 miles out of my first LWB chain, and it wasnt indicating full wear.

In this case, it appears that uncletam accidentally resurrected this thread by mis-posting here instead of a different toe clips/clipless pedal thread (?) that his post would seem to be in response to. Go figure.

With DALMAC approaching and the chain making some whirring sounds when I pedal, I checked the chain on my M5. It measured *almost* 1/16" of stretch over 12 inches. I opted to replace it now. The durned thing only had 2 1/2 seasons, or about 7500 miles on it. I've been pretty lax in keeping it lubed, so maybe if I shape up the next one will last longer.

In a similar vein, yesterday I ordered a loooong chain from Hostel Shoppe at a great price ($28): CH KMC Z9000 9spd 11ft 10in
There were only 2 in stock and today no KMC chains are listed on the site.
Not entirely sure I need a new chain, but I tend to replace chains and tires maybe a little early.
Ordered a SRAM cassette from Nashbar, also at an attractive price. Depending on how the current cassette on the V-Rex looks, I'll likely swap both out.

Some people posting on this thread think that because a chain is twice as long it should last twice as long. Don't forget, all of the chain moves at the same time no matter how long it is. It is true that any individual link on a short chain will bend twice as often while engaged with the cassette, derailleur, and chain ring cogs but a long chain seems to bounce more and that also causes bending albeit not as severe as around the cogged parts. Wear also has a lot to do with a person's cadence. The faster you pedal, the more often a chin link will engage a cog.

When my chain wears (stretches) I notice that it doesn't shift as smoothly. I have a fast cadence and used to get 2500 to 3000 miles before it was time to change the chain and cassette. At the time, I was oiling the chain often with those expensive wax lubricants you get at your bike shops. A few years ago I brought my bike into a bike shop with about 2500 miles on the chain and was told that the chain was marginal and will have to be changed soon. Then, instead of changing the chain I switched lubricants. I started to use chainsaw bar oil. I bought a gallon of the stuff for $15 US a few years ago and still had a lot left. 3000 miles later the bike shop told me that the chain was marginal. It almost stopped wearing. At the time, a lot of other parts were worn like the derailleur and the shifter and I was about to go on a long ride so I had the entire drive train replaced. That was well over 5000 miles ago and the chain is still good.

There are downsides to using chainsaw bar oil. It is sticky so dirt builds up sooner than with the other lubes while on dirt trails and it leaves a grease stain on the side of my ankle every time I ride. After a while though, the grease stain is not as bad and then I know its time to lubricate again. For less money, that lube works better than the expensive stuff. I do use a more soap now to clean my right ankle but soap is cheaper than the wax lubes. Pumice works the best of the soaps that I have tried.

That alone would make it unacceptable to me. We all have different priorities, and with the chain running within an inch or so of my knee, cleanliness is paramount. For the same reason, a lot of the fancy synthetic lubes just aren't on my list, no matter how much they claim to reduce wear.