Determining chain length?

Sheldon Brown says remove the chain from the derailleurs and run it around
large-large. Add 1 link. LBS says 2 links.

The teeth on this ride:
11-36 and 34-54 = 45

Before I choose one of the above and cut, I'm fishing for other opinions &
recommendations. (Not that there's anything wrong with the above advice...)

Open fire!

On 29 Sep, 06:28, Mike Cook wrote:
Sheldon Brown says remove the chain from the derailleurs and run it around
large-large. Add 1 link. LBS says 2 links.

The teeth on this ride:
11-36 and 34-54 = 45

Before I choose one of the above and cut, I'm fishing for other opinions &
recommendations. (Not that there's anything wrong with the above advice...)

Open fire!

Two 'links' are one link, or more precisely a block and link, although
the block of the 1/2" pitch chain is hollow so appears as a link.
Same instructions, different presentation.

As for the accuracy of the meaning, that's anyones guess given the
limited information you have presented. So it could well be perfect
in your application.

On Mon, 28 Sep 2009 22:28:24 -0700, Mike Cook
wrote:

Sheldon Brown says remove the chain from the derailleurs and run it around
large-large. Add 1 link. LBS says 2 links.

Try adding one link to a chain and see what happens.

On Sep 29, 3:35*am, Johnny Twelve-Point presented by JFT
wrote:
On Mon, 28 Sep 2009 22:28:24 -0700, Mike Cook
wrote:

Sheldon Brown says remove the chain from the derailleurs and run it around
large-large. Add 1 link. LBS says 2 links.

Try adding one link to a chain and see what happens.

Start with the long recommendation. Easy enough to take out another
link.

I have a bad combination on my bicycle. Going to small small is
pretty easy, no grinding from cross chaining. Problem is getting out
of the flipped back derailler. And can't take out a link because of
the 34 cog.

On Sep 29, 6:28*am, Mike Cook wrote:
Sheldon Brown says remove the chain from the derailleurs and run it around
large-large. Add 1 link. LBS says 2 links.

The teeth on this ride:
11-36 and 34-54 = 45

Before I choose one of the above and cut, I'm fishing for other opinions &
recommendations. (Not that there's anything wrong with the above advice....)

Open fire!

The process is complicated by the fact that some chains, the Rohloff
for instance, appreciate a little more slack than some others, for
instance the KMC 8X types. Of course, you can only increase or
decrease chain length in one inch increments (inner block plus two
sideplates -- "one" link in Sheldon-speak, "two" in the mouth of your
LBS) which is too coarse for this sort of sophisticated consideration;
effectively you can choose only the formula "plus one link" and must
make do with that. Such fine-tuning is what makes sliding or at least
horizontal frame ends so desirable when you're considering service
life and its much-sought corollary smoothness rather than the racer's
straight dropout capability.

Andre Jute
Visit Jute on Bicycles at
http://www.audio-talk.co.uk/fiultra/...20CYCLING.html

On Sep 29, 12:28*am, Mike Cook wrote:
Sheldon Brown says remove the chain from the derailleurs and run it around
large-large. Add 1 link. LBS says 2 links.

The teeth on this ride:
11-36 and 34-54 = 45

Before I choose one of the above and cut, I'm fishing for other opinions &
recommendations. (Not that there's anything wrong with the above advice....)

Open fire!

Install chain. Observe small small combo. Is there any sag? No? Done.

Install chain. Observe small small combo. Is there any sag? No? Done.

Is there any sag? Yes? ...?

Two 'links' are one link, or more precisely a block and link, although
the block of the 1/2" pitch chain is hollow so appears as a link.
Same instructions, different presentation.

Your terminology is more precise ("tomayto", "tomahto"). I presumed the
aforementioned sourced meant 2 or 4 "pieces" of chain.

As for the accuracy of the meaning, that's anyones guess given the
limited information you have presented.

Ask and the details shall be yours.

On Sep 29, 12:28*am, Mike Cook wrote:
Sheldon Brown says remove the chain from the derailleurs and run it around
large-large. Add 1 link. LBS says 2 links.

The teeth on this ride:
11-36 and 34-54 = 45

Before I choose one of the above and cut, I'm fishing for other opinions &
recommendations. (Not that there's anything wrong with the above advice....)

Open fire!

Why all this formula nonsense when you can just put the chain on the
bike and see if it fits. Wrap the chain around the big chainring and
around the biggest cog and through the derailleurs. Rear derailleur
cage should be stretched very forward, almost but not quite straight.
This is the length your chain should be. You do not want a short
chain that cannot get onto the big-big combination if you accidentally
shift to it. You will rip your derailleur hanger off if the chain is
too short. If the chain sags in the small-small combination, don't
worry. Bike will run just fine with the chain sagging onto the ground.

On 29 Sep, 19:07, Mike Cook wrote:
Two 'links' are one link, or more precisely a block and link, although
the block of the 1/2" pitch chain is hollow so appears as a link.
Same instructions, different presentation.

Your terminology is more precise ("tomayto", "tomahto"). I presumed the
aforementioned sourced meant 2 or 4 "pieces" of chain.

As for the accuracy of the meaning, that's anyones guess given the
limited information you have presented. *

Ask and the details shall be yours.

I'll make an assumption that you are using a modern rear derailler
with a swinging top pivot and you are in vertical dropouts and using
wide spaced chainrings. All this is far from ideal. The safest
option is to start with a long chain and see how it shifts after you
have run it for a bit. Avoid having a loose chain and make sure that
the chain does not bind when shifting to large large. After some
running on the road the mech will settle and may not produce the
required results. An appropriate length is generally thought to be
one which the pulley wheels align with a lean forward at the top.
During the shift they should lean back whether going up or down the
block. It would be nice to have this in all chainrings. Very wide
spaced rings may present problems even with long cage mechs.

Using long fork ends permits the user to locate the sprockets at the
most appropriate distance for best shifting.