|
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Does chain stretch really exist?
I have just measured 2 "old" 3/32 chains using the method described on
Sheldons page he http://sheldonbrown.com/chains.html One just came of of the "western flyer" I am rehabing, and the other came off my ofter beater road bike, and I could not even measure the "stretch" not even 1/32 of an inch. Is this a myth created and spread by the makers of chain to get us to buy more chain? Ken -- More of my mind dribblings: http://mind-dribble.blogspot.com/ And my homepage: http://kcm-home.tripod.com/ |
Ads |
#2
|
|||
|
|||
"Ken Marcet" wrote:
I have just measured 2 "old" 3/32 chains using the method described on Sheldons page he http://sheldonbrown.com/chains.html One just came of of the "western flyer" I am rehabing, and the other came off my ofter beater road bike, and I could not even measure the "stretch" not even 1/32 of an inch. Is this a myth created and spread by the makers of chain to get us to buy more chain? Quoting the very page you cited (and letting Sheldon save his voice): == "Chain "Stretch" Cyclists often speak of chain "stretch", as if the side plates of an old chain were pulled out of shape by the repeated stresses of pedaling. This is not actually how chains elongate. The major cause of chain "stretch" is wearing away of the metal where the rivet rotates inside of the bushing (or the "bushing" part of the inside plate) as the chain links flex and straighten as the chain goes onto and off of the sprockets. If you take apart an old, worn out chain, you can easily see the little notches worn into the sides of the rivets by the inside edges of the bushings. With bushingless chains, the inside edge of the side plate hole that rubs against the rivet has a smooth radius instead of a sharp corner. This probably contributes to the greater durability of bushingless chains. == It happens . . . and if it doesn't happen to you, it could happen to somebody that you love . . . . |
#3
|
|||
|
|||
On Fri, 4 Mar 2005 11:14:36 -0500, "Ken Marcet" wrote:
I have just measured 2 "old" 3/32 chains using the method described on Sheldons page he http://sheldonbrown.com/chains.html One just came of of the "western flyer" I am rehabing, and the other came off my ofter beater road bike, and I could not even measure the "stretch" not even 1/32 of an inch. Is this a myth created and spread by the makers of chain to get us to buy more chain? There is no meaningful stretch, only wear in the bearings that allow the chain to lengthen. Just measure them and replace when worn. It is just that simple. I don't know about any myths spread by the chain makers. I'd imagine they would be horrified if you accused their products of being so damn cheap and shoddy that they could be stretched by a cyclist. They are aware that their products wear. Ron |
#4
|
|||
|
|||
Ken Marcet wrote:
I could not even measure the "stretch" not even 1/32 of an inch. Not a myth. But since most bikes are never ridden even 1,000 miles, the chain on an older bike may not be elongated. Make sure the chain is under some tension when measuring. It's best to measure while the chain is on the bike and on the big chainring. Art Harris |
#5
|
|||
|
|||
As described by Sheldon Brown, chains wear at the pivot points.
However, there was one chain I saw that had some interesting wear features. This was a well used chain that had peened rivets. The peening was double parallel marks, looking somewhat like (=). This chain had several rivets with peening marks not parallel, but rather they were pointing off at an angle, more or less like (//). Normally the rivet is a tight press fit into the outer plate. However, it may have been that these holes became deformed and allowed the rivet to rotate. I wish I still had this chain sample. It had failed during a ride, and the rivets were easily removed, which may be a further indication of side plate deformity. |
#6
|
|||
|
|||
And here it is, folks . . . in all its photographic glory:
http://www.execulink.com/~dtierney/w...m#Chain%20wear or http://tinyurl.com/ysep8 |
#7
|
|||
|
|||
On Fri, 4 Mar 2005 11:14:36 -0500, "Ken Marcet"
may have said: I have just measured 2 "old" 3/32 chains using the method described on Sheldons page he http://sheldonbrown.com/chains.html One just came of of the "western flyer" I am rehabing, and the other came off my ofter beater road bike, and I could not even measure the "stretch" not even 1/32 of an inch. Is this a myth created and spread by the makers of chain to get us to buy more chain? Chain components don't stretch, but the pins, plates and rollers wear in a manner that causes the measured length over a number of links to increase. It's *very* real, but it's not uncommon for bikes that have not been ridden much to still have no measurable "stretch" even though they're many years old. Your WF probably falls into that category. -- My email address is antispammed; pull WEEDS if replying via e-mail. Typoes are not a bug, they're a feature. Words processed in a facility that contains nuts. |
#8
|
|||
|
|||
Per Neil Brooks:
http://www.execulink.com/~dtierney/w...m#Chain%20wear Nice piece of work. Thanks. -- PeteCresswell |
#9
|
|||
|
|||
Bicycles which are never ridden can't exhibit wear. A Western Flyer is the sort of bike which commonly is ridden for a few day after purchase and then parked in the back of the garage until one day it lands on the curb. Which is the point where you came in. -- Andrew Muzi www.yellowjersey.org Open every day since 1 April, 1971 Ken Marcet wrote: I have just measured 2 "old" 3/32 chains using the method described on Sheldons page he http://sheldonbrown.com/chains.html One just came of of the "western flyer" I am rehabing, and the other came off my ofter beater road bike, and I could not even measure the "stretch" not even 1/32 of an inch. Is this a myth created and spread by the makers of chain to get us to buy more chain? |
#10
|
|||
|
|||
Art Harris wrote:
Not a myth. But since most bikes are never ridden even 1,000 miles, the chain on an older bike may not be elongated. Make sure the chain is under some tension when measuring. It's best to measure while the chain is on the bike and on the big chainring. Also best to measure it clean, in case grit and sludge has taken up the slack between the pins and bushes. |
|
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
New bicycle idea | Bob Marley | General | 49 | October 7th 04 05:20 AM |
Chain snap, rider seriously injured | psycholist | Techniques | 42 | September 19th 04 06:25 PM |
Chain stretch and repair links | Doki | UK | 5 | April 14th 04 06:53 PM |
Actual data for the chain cleaning debate | TBGibb | Techniques | 60 | January 11th 04 02:32 AM |
FAQ | Just zis Guy, you know? | UK | 27 | September 5th 03 10:58 PM |