Another slack chain question

Just to be clear.

Chains undergo displacement.

Also we need to find a new name for 'moderator' now that Hippy has this role. Something that dosent contain the term 'moderate'.

↑ your girlfriend gave my cock a stretch. ↓

negating the need for a tug.....

.......throws self out window

This is rapidly becoming the sister to the Last Post Wins thread.

I'm outta here.....before His Highness hears of our larks. ;)

VHB&a.wFTW.

Chains don't stretch.

yeah they do.

Yes, chains get longer but how would the plate actually stretch - what is it, rubber?

Metal has the ability to deform under tension quite easily.

How do you think a bolt works? It stretches. I wouldnt discount the possibility of chain stretch based purely on the fact that it isnt rubber.

I have to re-tension after every other ride. I have DA track nuts and MKS chain tugs. It goes from 1cm to about 2.5cm slackness. Surely this is my chain stretching? (Joke. But I have NFI what it is.)

yup, defo stretch

I have to re-tension after every other ride. I have DA track nuts and MKS chain tugs. It goes from 1cm to about 2.5cm slackness. Surely this is my chain stretching? (Joke. But I have NFI what it is.)

either your chain is very *worn* or you aren't doing the bolts up tight enough.

if you kept up this rate of tightening for any length of time you'd pretty soon have popped off the end of the track ends as you allege it is a constant rate.

New chain.
Tight nuts.
Not an allegation, is a fact.
Obviously something is moving.

i mean, it sounds like its wearing/stretching a lot, and if it was it would be getting pretty close to the end of the dropouts, being about 2-3 inches longer than a brand new chain with same number of links, which isn't that unusual.

I have to re-tension after every other ride. I have DA track nuts and MKS chain tugs. It goes from 1cm to about 2.5cm slackness. Surely this is my chain stretching? (Joke. But I have NFI what it is.)

Weak arms. You're not doing your bolts tight enough.

I'll tighten your nuts (hello nurse!) and then if you can get them off without drawing blood I'll buy you a pint.

That's a very kind offer Hippy, thank you. I'll respectfully decline at this stage though.

i mean, it sounds like its wearing/stretching a lot, and if it was it would be getting pretty close to the end of the dropouts, being about 2-3 inches longer than a brand new chain with same number of links, which isn't that unusual.

2.5 inch of lengthening on a 110 link chain (55 inches) is c. 4.5% of wear which is no f*cking way usual. Your chain is fucked with 1% wear.

How long might this take?

Wippermann have been destruction testing 10 speed chains running 100rpm @ 52x17 gearing whilst spraying them regularly with water and sand.

50-100 hours only on this test in pretty unrealistic conditions designed to wreck chain as quickly as possible.

http://www.cantitoeroad.com/uploads/landingpage/connex/2010_chainwear_test_10speed.pdf

2.5 inch of lengthening on a 110 link chain (55 inches) is c. 4.5% of wear which is no f*cking way usual. Your chain is fucked with 1% wear.

How long might this take?

Wippermann have been destruction testing 10 speed chains running 100rpm @ 52x17 gearing whilst spraying them regularly with water and sand.

50-100 hours only on this test in pretty unrealistic conditions designed to wreck chain as quickly as possible.

http://www.cantitoeroad.com/uploads/landingpage/connex/2010_chainwear_test_10speed.pdf

perhaps 2-3 inches is exaggerating, but i don't think it is impossible to do. i have certainly had old chains be 1.5inches longer than a brand new one of the same number of links.

Just when I had accepted Smallfurry's explanation of chain displacement versus chain stretch, Halfords go and throw me back into that same fetid state of confusion. Damn you Halfords!!

See the third bullet point under FEATURES AND BENEFITS in the photo.

Knowing that hippy is a mechanic at Halfords, I await his official response from that company.

1 Attachment

the kmc710 still stretches

Chains don't stretch.

I think you'll find that your employers (Halfords) say they do.

Thanks.

My employers? They all drive Bentleys and wouldn't know a bike if it bit them on the arse.

Lucky I know best.

surely if the hole grow wider the pins fall out right? they dont though do they, no. dam next tim ei get a new chain im gonna break out my digi calipers and measure that sucker and keep measuring it till i replace it. we'll see whos right, im sure they stretch too, either that or you lot are crap teachers cos i still dont understand how a worn chain can be physically longer than an unworn chain without doing the stretch thing...

i still dont understand

here is your problem

:d

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.

You can see how the rivet of this unusually badly worn chain has been worn away.
Note also how the roller has flopped out of position.

The reason the roller flops around is that the "bushing" part of the chain has been eroded away.
No doubt the inner surface of the roller has become enlarged as well.

http://www.sheldonbrown.com/chains.html

Riders often speak of "chain stretch" a technically misleading and incorrect term. Chains do not stretch, in the dictionary sense, by elongating the metal by tension. Chains lengthen because their hinge pins and sleeves wear. Chain wear is caused almost exclusively by road grit that enters the chain when it is oiled. Grit adheres to the outside of chains in the ugly black stuff that can get on ones leg, but external grime has little functional effect, being on the outside where it does the chain no harm.

The black stuff is oil colored by steel wear particles, nearly all of which come from pin and sleeve wear, the wear that causes pitch elongation. The rate of wear is dependent primarily on how clean the chain is internally rather than visible external cleanliness that gets the most attention.

Only when a dirty chain is oiled, or has excessive oil on it, can this grit move inside to causes damage. Commercial abrasive grinding paste is made of oil and silicon dioxide (sand) and silicon carbide (sand). You couldn't do it better if you tried to destroy a chain, than to oil it when dirty.

http://www.sheldonbrown.com/brandt/chain-care.html

Now, find someone as qualified as these two who disagrees.