Where to buy a 120 link chain?



Flatbardave

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Dec 16, 2015
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My Kona rove (2 x 10) 50/34 x 11-36 has a 120 link chain.
Only 400 mile on it so far but was looking to buy a KMC SL 120 link chain
Can only find 116 link,

Where to find to get a 120 link KMC SL or 120 link chain ?
If I have to splice 2 chains together, how far apart should the 2 "Q"-links be ?
 

dabac

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Sep 16, 2003
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The reason 120 links are hard to find is that they are rarely needed. Before you do anything else, verify that you actually need it. Being delivered with one is not reliable proof that this is what you need.
There are plenty of web info on "bicycle chain sizing". Take your pick.
If you really do need 120 links, you can get bulk packs from places like this:http://www.chickencycles.co.uk/index.php?cat=15&sub=18
Or maybe ask around at shops, see which carries bulk packs and ask them to sell you some. Or ask fellow riders and home mechanics about cutoffs.
Or buy two and stick them together, as you've already considered.
Spacing the quicklinks out or not doesn't matter.
Remember the saying about no chain being stronger than its weakest link?
Well, it's the literal truth.
Mid-run, between sprocket and chainring, each link has to be strong enough, as it won't/can't receive any support from the other links of from the other teeth of the sprocket/chainring.
I'm a bit of a symmetry addict, so part of me would urge me to put them at equal distances.
But from an engineering perspective, it really doesn't matter.
 
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alfeng

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Jul 23, 2005
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My Kona rove (2 x 10) 50/34 x 11-36 has a 120 link chain.
Only 400 mile on it so far but was looking to buy a KMC SL 120 link chain
Can only find 116 link,

Where to find to get a 120 link KMC SL or 120 link chain ?
If I have to splice 2 chains together, how far apart should the 2 "Q"-links be ?

FWIW. Others may disagree ... and, they may be right ...

BUT, it is MY impression that Shimano shifters work best when the drivetrain has the properly sized (in width ... aka "speed") Shimano chain.

BTW. While I have some "other" (non-Shimano) chains, Shimano chains are probably the best value AND the only chain which I recommend ...

I prefer to use Campagnolo shifters (yes, they can be used with Shimano derailleurs!) AND my preference is for Shimano chains.​
 
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cyclintom

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Jan 15, 2011
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Some bike shops buy their chain in rolls and can provide any length you like.

But as a word of advice - it is very unlikely that bike requires a chain that long. Cross-chain the bike, large-large, and look at the position of the rear derailleur arm. I think you will find that it is no more than vertical. Then cross-chain it small-small and I think that you will find slack in the chain. The entire reason for using a long arm rear derailleur is to prevent that slack. I would bet that you would find that 116 links would work fine.

You mileage may vary.
 

oldbobcat

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Aug 31, 2003
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I had to look up the Kona Rove to see what kind of bike it is:

rove2015.jpg
There's nothing about it that really requires a really long chain. The 36t cassette cog is a bit large, but not that large, and the chain stays are not long. Generally, really long chains are only needed for long stays like cargo bikes and Electra Townies. I have a hunch the chain that's on the bike is too long anyway.

If the old chain is off the bike, loop it around the big chain ring and the largest cog, bypassing the rear derailleur. For multiple chain rings, the two ends should overlap by two (one pair of) links. If the chain is still on the bike, shift into big-big, pull up the slack in front of the rear derailleur and "fold" the chain to see how much overlap there is.

SRAM, who also use a connecting link, has good manual on chains and cassettes here: https://sram-cdn-pull-zone-gsdesign...00_rev_a_user_manual_cassettes_and_chains.pdf
 

oldbobcat

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By the way, alf, how does one hubbub the cable to mate Campagnolo shifters with SRAM derailleurs? Or are you recommending a derailleur swap while the bike is on the work stand, anyway? And if we're swapping derailleurs, do we want Shimano or Campagnolo?
 

alfeng

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Jul 23, 2005
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By the way, alf, how does one hubbub the cable to mate Campagnolo shifters with SRAM derailleurs? Or are you recommending a derailleur swap while the bike is on the work stand, anyway? And if we're swapping derailleurs, do we want Shimano or Campagnolo?

You may recall that at one time, the Campagnolo 10-speed shifters & SRAM 10-speed shifters were theoretically interchangeable for the alternative rear derailleur & respective indexing ...

So, if YOU knew someone who wanted to convert his-or-her 10-speed SRAM bike to use with Campagnolo shifters, or vice-versa ( :eek: ), then s/he should be good to go after replacing the SRAM 10-speed shifters with Campagnolo 10-speed shifters AND/OR find that the SRAM 10-speed shifter was presumably fine with the Campagnolo rear derailleur & 10-speed Campagnolo Cassette indexing ...

However, because SRAM has a who-needs-trim front shifter, a Campagnolo OR Shimano front derailleur would need to be replaced with the appropriate SRAM front derailleur.​

I can't say how iffy shifting would be with the various (as in, non-Campagnolo) 11-speed shifters other than to note that the ramping on the Cogs on all post-2000 Cassettes means that if the Stops are set properly on the rear derailleur, then it will shift fine, but may not index onto all 11 Cogs (i.e., one Cog may-or-may-not be bypassed).

I suppose that IF one needed to (or could) hubbub a SRAM rear derailleur then it would be necessary to "cannibalize" a molly hook from a Shimano rear derailleur -- or try to find-or-fabricate an equivalent --- and, proceed, accordingly..​

Now, as to whether a person should choose-or-use Campagnolo or Shimano derailleurs ....

I love Shimano derailleurs ...

Except for XTR & Dura Ace, I think they are generally a better value for the money than Campagnolo derailleurs.
So, my preference & general recommendation would for a standard pull SLX or XT rear derailleurs for NON-racers over Campagnolo derailleurs regardless of shifters UNLESS "cosmetics" are an issue (nothing wrong with THAT!).​
 
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Flatbardave

Member
Dec 16, 2015
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Hay
Youns may be onto something.
"I might be crying before I'm hurt "

chain stay = 17.25, 50t crank, 36t cassette
DSCF5426.JPG

Using the "Park Tool" chain formula:

Simple Equation: L = 2 (C) + (F/4 + R/4 + 1)

L = Chain length in inches. Round the final result to closest whole inch figure.
C = Chain stay length in inches, measure to closest 1/8". Use chart above to find decimal measurement.
F= Number of teeth on largest front chainring.
R= Number of teeth on largest rear cog.

Example: A bike has a 42-32-22 front chainring set up. Use only the 42 for the equation. The rear cog set has 32 teeth on the largest cog. The bike measures 16-3/8" from the center of the rear axle to the center of the crank bolt. The decimal equivalent for 16-3/8" is 16.375 inches.

2(17.25) + ( 50/4 + 36/4 +1 ) = chain length = 58
34.5 + 22.5 = 57
Each link is 1/2"

57" X 2 = 114

I'm gonna slowly remove a 2 links at a time & see what it looks like on 50-36.

Well first I'm gonna count to verify the paperwork I got is correct,
Paperwork says "chain, Sram , PC 1071, 10 speed ,120 link ....$59.99 "

Trust but verify !!! Now gonna get it down & mark & actually count . DUH :oops:
 

Flatbardave

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Dec 16, 2015
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There's nothing about it that really requires a really long chain. The 36t cassette cog is a bit large, but not that large, and the chain stays are not long. Generally, really long chains are only needed for long stays like cargo bikes and Electra Townies. I have a hunch the chain that's on the bike is too long anyway.

If the old chain is off the bike, loop it around the big chain ring and the largest cog, bypassing the rear derailleur. For multiple chain rings, the two ends should overlap by two (one pair of) links. If the chain is still on the bike, shift into big-big, pull up the slack in front of the rear derailleur and "fold" the chain to see how much overlap there is.

SRAM, who also use a connecting link, has good manual on chains and cassettes here: https://sram-cdn-pull-zone-gsdesign...00_rev_a_user_manual_cassettes_and_chains.pdf


Good catch. Thanks :)

What I found, it was 120 links
Went low low : then hi/hi
DSCF6231.JPG DSCF6230.JPG

RDR is not adjusted properly
Look at in low low, doubled up on itself & hi hi, almost totally maxed out the arm
The jockey idler is way back, not under the cassette.

Adjusted the RDR to get the jockey idler close to the cassette gears
Started gaining chain on the hi hi position

Ended up removing 4 links ,
DSCF6238.JPG

Compare lo lo before/after, much better
Might could've got more but it looks pretty good with a 116 link chain
in Lo Lo the RDR Idler is under the cassette now
DSCF6234.JPG


& still have a little slack on hi hi
DSCF6235.JPG

Gotta shift much better too.
 

oldbobcat

Well-Known Member
Aug 31, 2003
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Compare lo lo before/after, much better
Might could've got more but it looks pretty good with a 116 link chain
in Lo Lo the RDR Idler is under the cassette now

Gotta shift much better too.
116 looks about right to me, too.
 

Flatbardave

Member
Dec 16, 2015
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New from bike shop
Surprises me that it was adjusted & set up that way.
errr...... maybe it wasn't adjusted ......

Finding out it's god to know a little about the mechanical
workings of a bike.

Pays to double check

Thanks guys.

Good learning day !!!

Can find multiple types of 10 speed, 116 link chain all day
off the shelf or online
:)
 

alfeng

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Jul 23, 2005
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By the way, alf, how does one hubbub the cable to mate Campagnolo shifters with SRAM derailleurs? Or are you recommending a derailleur swap while the bike is on the work stand, anyway? And if we're swapping derailleurs, do we want Shimano or Campagnolo?

BTW ...

Although I have said the following, before, I think that it is worth repeating ...

It is MY opinion that it DOES NOT require any finesse to adjust a front derailleur which is mated to a Campagnolo front shifter ...

Either THAT is true or I must be a heck of a Wrench! :)

As elegant as SRAM's Double Tap mechanism is AND as efficient as many people feel SRAM shifters are in use ...

I think that you (oldbobcat) may want to finally consider a pair of Campagnolo shifters + housing & cables on your 2016 "shopping list" because even though you indicated trying a Campagnolo equipped bike, once (?), on a ride, I think that your appreciation will be amplified many-times-over if you "live" with a set for a month-or-so of once-in-awhile riding-and-wrenching.

It's okay for YOU to step-into-the-light!
 

moneyman

Member
Oct 6, 2015
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I have found them in special bike equipment shops but they are in my opinion quite rare.