Chain snap, rider seriously injured

On 16 Sep 2004 05:45:33 -0700, (Art Harris)
wrote:

A Muzi wrote:

That didn't 'just happen'. A link was not joined properly.

We strongly advise use of snaplinks and attempt to dissuade
customers from setting rivets in modern chain exactly
because of your and similar incidents.

There are still a lot of riders who insist they don't need
some sissy snaplink. They're perfectly capable of setting a
measly chain rivet with the same tool they've used for 25
years thank you.

Problem is, chain is different and setting a rivet now is
just not safe.

I've never used a snap link so maybe I'm missing something. But
doesn't the snap link have to be connected to the rest of the chain
initially by using a chain tool? If so, an improperly installed pin
could still cause a failure.

I admit I like the Shimano "special pin" method.

Art Harris

Dear Art,

Most bicycle snaplink/quicklink/powerlink pieces assemble by
hand, unlike the special pin, which needs a chain tool.

A motorcycle-style masterlink falls in between these two
extremes in that a pair of needlenose pliers is needed to
install and remove the elongated circlip that holds the
sideplate on.

Carl Fogel

In article , kantspel
writes:

So your saying I should probably replace that chain I repaired by
stomping the pin back in with my foot?

Are you serious?

Tom Gibb

In article , "psycholist"
writes:
snip
I have really thought all about how a chain can break
suddenly. Having a chain break was strange to me,
until a couple of people have mentioned that they know
people who have had chains break. Steve's chain is not
old or worn. It looks as if one plate came off the pin
and the chain pulled apart. No metal actually snapped.
His chain is not one of the newer lightweight chains
that are marketed these days, those with drilled or
thinner plates and/or hollow pins that reduce weight.
Also, a lot of the chains these days have one link
that can be moved or taken apart along side the road.
I would think these chains are weaker then the old
conventional chains where the pin is forced into place
with a tool. I looked up the technical information on
Steve's particular chain. It is one of their strongest
chains. They make his chain with and without a "quick
link" that can be adjusted by hand without a tool. I
do not know if he had a "quick link". If he did, it is
along side the road in Six Mile. I suspect his chain
had all pins that are forced into place with pressure.
You have to have two pins break in order to lose a
link of chain. It appears the chain only came apart in
one place and no links are missing. It is just one of
those things that happens, I suppose.
snip

The only time I had a chain break was when I, frustrated with the new fangled
"Power Link" pressed a rivet part way out so I could clean the chain and then
re-assembled it. My thought is that SRAM chains are not intended to have a
rivet pressed back in. I don't do so any more. I suspect that is what
happened to your friend. It appears to me that all you have to do is loose one
end of the rivet and it's over.

Tom Gibb

In article , "A7N8X-X"
writes:

I've got a SRAM chain that has a removable link, but I haven't put it on
yet. I bought it for when my cassette wears out. Are the removable links
pretty reliable?

I've been using them for years with no trouble.

Tom Gibb

kantspel said...

So your saying I should probably replace that chain I repaired by
stomping the pin back in with my foot?

who needs sissy snaplinks or chaintools

No, that's OK. If you do anything but stomping it back in with your
foot, use a snap link.

On 16 Sep 2004 05:45:33 -0700, (Art Harris) wrote:

A Muzi wrote:

That didn't 'just happen'. A link was not joined properly.

We strongly advise use of snaplinks and attempt to dissuade
customers from setting rivets in modern chain exactly
because of your and similar incidents.

There are still a lot of riders who insist they don't need
some sissy snaplink. They're perfectly capable of setting a
measly chain rivet with the same tool they've used for 25
years thank you.

Problem is, chain is different and setting a rivet now is
just not safe.

I've never used a snap link so maybe I'm missing something. But
doesn't the snap link have to be connected to the rest of the chain
initially by using a chain tool? If so, an improperly installed pin
could still cause a failure.

No, and that's the beauty part.

I admit I like the Shimano "special pin" method.

Better than trying to re-feed the old pin back in.

Ron

TBGibb wrote:
In article , kantspel
writes:


So your saying I should probably replace that chain I repaired by
stomping the pin back in with my foot?


Are you serious?

Tom Gibb

about fixing it or riding it? Yes, you can fix a chain that way. Get
the pin lined up just right, put something hard on top of it (a flat
rock in this case) and stomp. Worked on the first shot for me.

As for continuing to ride on it...no, i wussed out. It got me home and
I promply replaced the chain.

In article , kantspel
writes:

In article , kantspel

writes:


So your saying I should probably replace that chain I repaired by
stomping the pin back in with my foot?


Are you serious?

Tom Gibb

about fixing it or riding it? Yes, you can fix a chain that way. Get
the pin lined up just right, put something hard on top of it (a flat
rock in this case) and stomp. Worked on the first shot for me.

The rock helps. I am still impressed and I'm gonna keep that trick in mind.

As for continuing to ride on it...no, i wussed out. It got me home and
I promply replaced the chain.

I call that prudent, not wussy.

Tom Gibb

On Wed, 15 Sep 2004 15:48:14 -0400, Weisse Luft wrote:


I bet the problem was with the rejoining method. Most chains require
careful assembly to ensure the pin is correctly reinstalled. If the
chain tool's drive pin is just slightly larger than the chain pin,
removal will swage the hole in the side plate a few thiousandth's
larger, resulting in a poor fit.

A worn chain tool will also do this as the drive pin becomes slightly
"mushroomed" with use.

Still one more problem is incorrect setting. In old days, one jsut
needed to work the stiff link out with lateral pressure and flexing. Not
so today as the stiffness may result in the pin pulling out the wrong
way. Most modern chain tools have an additional "fence" to set the
chain clearance. See the complete instructions.

If you use one of the quick links, the chain tool use becomes less
critical. Most quick links are adequately strong but I have had one
come apart in use. I found the parts and was able to reassemble.


I've seen maybe 4 broken or damaged chains in 32 years of riding. I saw
two of them on the Covered Bridge Metric this Aug. 15th. And neither of
the people who had the broken chains had ever done any disassembly of
their chains. In fact, one of the two, a young woman, told me she never
actually has done any cleaning on her bike at all - what work's been done
has all been at the LBS.

On Thu, 16 Sep 2004 08:45:33 -0400, Art Harris wrote:


I've never used a snap link so maybe I'm missing something. But doesn't
the snap link have to be connected to the rest of the chain initially by
using a chain tool? If so, an improperly installed pin could still cause
a failure.

I admit I like the Shimano "special pin" method.


And I hate them so much I gave up on Shimano chains entirely for a while
(I've now got one with a 3rd party link, and, having been freed from the
irritation of that blankeyblank special pin, I find it's actually a quite
nice chain after all). No you do not need to use a chain tool to install
the link. If you shorten the chain, of course, you do need to push a pin
out with a chain tool. But the SRAM link just fits in by hand. And it
works great, too.