chain twist

[Ted Heise]

Had a unique experience out riding today. On a longish (for here)
downhill I shifted quickly from small to large ring, and threw the
chain off the outside of the large ring. A double ring with all
Shimano 10 sp components. So I put the shifter back to the small
ring, and that threw it off to the inside. (I know, the derailer
limits aren't set right).

I tried shifting the chain back onto the chain rings, but it
wouldn't go. After coasting to a stop, I reached down to lift the
chain back onto the small ring--pulling it outward, against the
inner side of the big ring and dropping it onto the small ring.
It just wouldn't catch on the small ring, so I got off the bike to
look more closely.

I was surprised to see the chain had a roughly 45 degree twist in
the run from the top of the cassette to the front der. I thought,
"I must have bent the shit out of it!" Figuring I's see if I
could bend it back so I could get home, I worked the chain back
off the outside of the big ring and started bending the free run
of chain. Lo and behold, the whole thing snapped, and ended up in
the proper orientation. Somehow it must have untwisted when I
applied the force to it.

After that, I was able to ride the remaining 10 miles home, and it
seemed to shift okay. I have never seen anything like this, or
even heard of it--but I have to think other probably have?

Also, I assume I ought to toss that chain?

--
Ted Heise <the...@panix.com> West Lafayette, IN, USA

[AMuzi]

First off thanks for your refreshing honesty:

"the derailer limits aren't set right"

Secondly, to put a dropped chain back on a chainring, hold
the link against a tooth on the bottom and spin the crank
backwards. Minimal crud on fingers.

Finally, replace your chain. A chain failure standing up is
a rider injury and even not standing can be dangerous.

Oh, and yes damaged/twisted chain is a known thing, not all
that unusual, although more often from rear changer in spokes.

--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971

[Tom Kunich]

Ted, I suspect that you broke the chain. Close inspection will probably reveal that one link is pulled off of its rivet. Just replace the chain, set the proper limits and by all means get a dog fang or other appropriate inside chain fall-off protector.

[Catrike Rider]

On Sun, 28 May 2023 14:23:41 -0700 (PDT), Tom Kunich
<cycl...@gmail.com> wrote:

Yes, it's got to be broken. Find the bad link and replace it, unless
the chain is close to full replacement.

[John B.]

How much does a new chain cost? I looked at Amazon and find a "SHIMANO
Tiagra 10 Speed Road Bicycle Chain" listed for $26.14. Is that "big
money" in the U.S. these days?
--
Cheers,

John B.

[Ted Heise]

On Sun, 28 May 2023 15:51:54 -0500,
AMuzi <a...@yellowjersey.org> wrote:
> On 5/28/2023 3:21 PM, Ted Heise wrote:

> > I was surprised to see the chain had a roughly 45 degree twist
> > in the run from the top of the cassette to the front der. I
> > thought, "I must have bent the shit out of it!" Figuring I's
> > see if I could bend it back so I could get home, I worked the
> > chain back off the outside of the big ring and started bending
> > the free run of chain. Lo and behold, the whole thing
> > snapped, and ended up in the proper orientation. Somehow it
> > must have untwisted when I applied the force to it.

> First off thanks for your refreshing honesty:
> "the derailer limits aren't set right"

Of course. "A man should never be ashamed to own that he has been
in the wrong, which is but saying in other words that he is wiser
today than he was yesterday."

> Secondly, to put a dropped chain back on a chainring, hold the
> link against a tooth on the bottom and spin the crank
> backwards. Minimal crud on fingers.

Well, maybe so. But I've been dropping it across the top and
spinning it forward for decades with pretty good results. It
helps that I use parrafin wax instead of any grimy lube.

> Finally, replace your chain. A chain failure standing up is a
> rider injury and even not standing can be dangerous.

Will do. This was my thought as well, but I wanted to get some
confirmation before throwing out something that might be ok.

> Oh, and yes damaged/twisted chain is a known thing, not all
> that unusual, although more often from rear changer in spokes.

Well, I've bent/twisted individual links before, especially when
the chain's dropped inside the rings on the tandem. Lots of
torque applied by those bikes! This was something entirely
different. No individual links showed any sign of damage or
twisting after the chain popped back into the untwisted config.
It was like a rubber band that had in inner surface turned outward
in a half twist about the line of the chain...

http://panix.com/~theise/twisted.jpg

[Catrike Rider]

On Mon, 29 May 2023 05:42:00 +0700, John B. <sloc...@gmail.com>

But it's so easy to fix it. Most people have everything they need
right at in their shop.

[Ted Heise]

On Mon, 29 May 2023 05:42:00 +0700,

John B <sloc...@gmail.com> wrote:
> On Sun, 28 May 2023 17:39:46 -0400, Catrike Rider
> <sol...@drafting.not> wrote:
> >On Sun, 28 May 2023 14:23:41 -0700 (PDT), Tom Kunich
> ><cycl...@gmail.com> wrote:
> >>On Sunday, May 28, 2023 at 1:21:26?PM UTC-7, Ted Heise wrote:

> >>> Had a unique experience out riding today.

> >>> I was surprised to see the chain had a roughly 45 degree
> >>> twist in the run from the top of the cassette to the front
> >>> der. I thought, "I must have bent the shit out of it!"
> >>> Figuring I's see if I could bend it back so I could get
> >>> home, I worked the chain back off the outside of the big
> >>> ring and started bending the free run of chain. Lo and
> >>> behold, the whole thing snapped, and ended up in the proper
> >>> orientation. Somehow it must have untwisted when I applied
> >>> the force to it.
> >>>
> >>> After that, I was able to ride the remaining 10 miles home,
> >>> and it seemed to shift okay. I have never seen anything like
> >>> this, or even heard of it--but I have to think other
> >>> probably have?

> >>Ted, I suspect that you broke the chain. Close inspection will
> >>probably reveal that one link is pulled off of its rivet. Just
> >>replace the chain, set the proper limits and by all means get
> >>a dog fang or other appropriate inside chain fall-off
> >>protector.
> >
> >Yes, it's got to be broken. Find the bad link and replace it,
> >unless the chain is close to full replacement.

Guys, I'm pretty sure nothing was frankly broken. If something
was broken, it seems unlikely I could have ridden the 10 miles
home. I suspect the twisting was distributed across much of the
length of the chain, so no individual link bore the brunt of it.

> How much does a new chain cost? I looked at Amazon and find a
> "SHIMANO Tiagra 10 Speed Road Bicycle Chain" listed for $26.14.
> Is that "big money" in the U.S. these days?

No, not for me anyway. My hesitation was not unwillingness to
spend the money, rather a preference to not needlessly add to the
waste stream that flows from my existence into the rest of the
world.

[John B.]

On Sun, 28 May 2023 19:38:14 -0400, Catrike Rider

True. But chains seldom wear out a single link. If a link was so worn
that it allowed the chain to twist as severely, as the original poster
described, it is logical to assume that the whole chain is worn.

One could, I suppose, repair the twisted link and then repair the next
twisted link when it failed, and then the next, and the next.

--
Cheers,

John B.

[Ted Heise]

Okay, on closer inspection, there is apparently a link or two that
kept some residual twist, because there is a short run of 2-3
links that move closer to the inner part of the derailer cage when
they move through it. An almost imperceptible amount of twist of
the chain can be seen just before and just after this lateral
movement.

[AMuzi]

In The Olden Days with classic roller chain for derailleurs
(8mm wide for 4, 5, 6 freewheels) removing and replacing a
link was straightforward and sensible.

For 8, 9, 10, 11, 12 or 13 speed chain, rivets are
essentially flush and a tighter fit in thinner sideplates,
making chain repair unreasonable and possibly unsafe.

One _could_ certainly re use innies with more snaplinks, but
as you note new chain is not all that expensive

[AMuzi]

If you're curious and still have that chain, view it end-on.
The damaged link(s) will be glaringly obvious.

[AMuzi]

Sight the chain from the end. You'll instantly spot the
damaged link(s).

[AMuzi]

It's not a worn link. It's a damaged (twisted sideplates)
link. Or more than one perhaps but usually only one.

[Catrike Rider]

I added links (9sp) just recently when I replaced most of my drive
train. I did it once out on the trail after I stupidly broke the chain
by rolling backwards half-way through downshift.

[Ted Heise]

On Mon, 29 May 2023 08:26:10 -0500,
AMuzi <a...@yellowjersey.org> wrote:

> On 5/28/2023 5:42 PM, John B. wrote:
> > On Sun, 28 May 2023 17:39:46 -0400, Catrike Rider
> > <sol...@drafting.not> wrote:
> >> On Sun, 28 May 2023 14:23:41 -0700 (PDT), Tom Kunich
> >> <cycl...@gmail.com> wrote:
> >>> On Sunday, May 28, 2023 at 1:21:26?PM UTC-7, Ted Heise wrote:

> >>>> [story of twisted chain]

> >>> Ted, I suspect that you broke the chain. Close inspection
> >>> will probably reveal that one link is pulled off of its
> >>> rivet. Just replace the chain, set the proper limits and by
> >>> all means get a dog fang or other appropriate inside chain
> >>> fall-off protector.
> >>
> >> Yes, it's got to be broken. Find the bad link and replace it,
> >> unless the chain is close to full replacement.
> >
> > How much does a new chain cost? I looked at Amazon and find a
> > "SHIMANO Tiagra 10 Speed Road Bicycle Chain" listed for
> > $26.14. Is that "big money" in the U.S. these days?
>
> In The Olden Days with classic roller chain for derailleurs
> (8mm wide for 4, 5, 6 freewheels) removing and replacing a link
> was straightforward and sensible.
>
> For 8, 9, 10, 11, 12 or 13 speed chain, rivets are essentially
> flush and a tighter fit in thinner sideplates, making chain
> repair unreasonable and possibly unsafe.
>
> One _could_ certainly re use innies with more snaplinks, but as
> you note new chain is not all that expensive

Good accounting (as usual), but I noticed you left out 7 speeds.
Presumably not many problems with pin manipulation?

And yes, I pushed out and reseated many a pin back in my 6-speed
days. I also did it on my 9-speed setups--until a chain came
apart while my wife and I were doing a honkin' standup climb on a
steepish hill in the Bloomington, IN area. After that experience,
I went entirely to quick links. Fortunately, neither of us was
hurt.

[Ted Heise]

On Mon, 29 May 2023 08:35:22 -0500,

AMuzi <a...@yellowjersey.org> wrote:
> On 5/28/2023 6:38 PM, Ted Heise wrote:
> > On Sun, 28 May 2023 15:51:54 -0500,
> > AMuzi <a...@yellowjersey.org> wrote:
> >> On 5/28/2023 3:21 PM, Ted Heise wrote:
> >
> >>> I was surprised to see the chain had a roughly 45 degree
> >>> twist in the run from the top of the cassette to the front
> >>> der. I thought, "I must have bent the shit out of it!"
> >>> Figuring I's see if I could bend it back so I could get
> >>> home, I worked the chain back off the outside of the big
> >>> ring and started bending the free run of chain. Lo and
> >>> behold, the whole thing snapped, and ended up in the proper
> >>> orientation.

> >> Finally, replace your chain. A chain failure standing up is
> >> a rider injury and even not standing can be dangerous.
> >
> > Will do. This was my thought as well, but I wanted to get
> > some confirmation before throwing out something that might be
> > ok.

Done. The bike rode fine today, as expected.

> >> Oh, and yes damaged/twisted chain is a known thing, not all
> >> that unusual, although more often from rear changer in
> >> spokes.
> >
> > Well, I've bent/twisted individual links before, especially
> > when the chain's dropped inside the rings on the tandem.
> > Lots of torque applied by those bikes! This was something
> > entirely different. No individual links showed any sign of
> > damage or twisting after the chain popped back into the
> > untwisted config. It was like a rubber band that had in inner
> > surface turned outward in a half twist about the line of the
> > chain...
> >
> > http://panix.com/~theise/twisted.jpg
>
> If you're curious and still have that chain, view it end-on.
> The damaged link(s) will be glaringly obvious.

I had laid it in a line along my nice level concrete garage floor,
and looked at it from above--with one plate side against the floor
and with a 90 degree rotation about its length. In the latter
position, there was one location that looked to sway a bit.

Your technique worked great Andrew. One link was clearly bent.
Was that bit of knowledge handed down to you, or did you figure it
out on your own. Either way, it's good--thanks!

[Ted Heise]

Spot on, again. It was just one.

[Mike A Schwab]

On Monday, May 29, 2023 at 3:37:06 PM UTC-5, Ted Heise wrote:
> Good accounting (as usual), but I noticed you left out 7 speeds.
> Presumably not many problems with pin manipulation?
>

<deleted> --

> Ted Heise <the...@panix.com> West Lafayette, IN, USA

Some 7 speeds and 4-6 were cassette & freewheel on threaded hub. Became prone to breaking axles.

Some 7 speeds and 8+ are cassettes on freewheel in hubs.

https://www.sheldonbrown.com/free-k7.html

[AMuzi]

Not definitive.

Sevens (since the Sedisport) have more prominent rivets than
later chain but not as simply removed/pressed as classic
chain. A guy probably could with reasonable care but I still
don't think it's good practice.

As you note chain failure can be a real risk and not always
harmless.

[AMuzi]

Mechanics generally assess chain damage with the bike upside
down and the run of the chain at eye level. Sighting from
one end, one just backpedals to see if there is any
variance. That's a common check after rear changer in spokes
for example.

[AMuzi]

On 5/29/2023 4:06 PM, Mike A Schwab wrote:

The first cassettes (Chiorda, DNB, Shimano) were five speed
and cassette systems now span to 13 speeds.

Freewheels began with three, quickly changed to four and
then the wildly popular in 5, 6, 7 until cassettes improved.

There are also 8 and 10 freewheels (I assume nine but have
never seen one).

The subject however was chain.

The first 'narrow' chain was made by HKK for the Suntour
Ultra systems. As more makers added sevens (which are all
narrow spaced), Sedis (Sedisport) and then promptly everyone
else entered the narrow chain manufacturing business, and
here we are.

Not an exhaustive list but a representative sample:
http://www.yellowjersey.org/photosfromthepast/MANYCHAN.JPG

[Tom Kunich]

Good new chains are pretty expensive but the results of a broken chain can be serious injury or even in the extremes - death. That makes chains REAL CHEAP.

[Frank Krygowski]

On 5/29/2023 4:37 PM, Ted Heise wrote:
>
> And yes, I pushed out and reseated many a pin back in my 6-speed
> days. I also did it on my 9-speed setups--until a chain came
> apart while my wife and I were doing a honkin' standup climb on a
> steepish hill in the Bloomington, IN area.

I rode from here to Bloomington many years ago, and rode around there.
Yes, Bloomington's got hills. I remember 'em.

_Breaking Away_ was filmed there. Fun movie.

--
- Frank Krygowski