Which is the better chain length? Only difference between the two is one pair of links. Both seem OK to me, but one looks slightly on the long side, one slightly on the short. Which would you choose?
Background: I'm setting up a chain on a 105 system - different size cassette and chainrings to the old setup so can't just copy the old chain. Yes, it's already been out for a ride, hence why it's not clean.
Slightly shorter
Big/Big
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Small/Small
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Slightly longer
Big/Big
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Small/Small
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what chain rings have you got up front ? if it's a double I wouldn't be bothered about either (probably go with the second) because you shouldn't ever be in either.
Double (compact 50-34). Agree, would not plan on being in either on purpose however it does happen.
Both seem OK, so I'm just wondering which is "better".
Longer.
The first one looks at full stretch.
I see what you mean re one a bit long, one a bit short.
I'd go longer one.
But the shorter one looks like it should be ok, the chain through the jockeys still has a bit to give, and you have no suspension movement to worry about. Will the jockey cage still move a bit more on the big big?
Thanks for the feedback. I'm tending towards the longer as being the better option.
For comparison - rear mech at "full stretch" (top run of the chain pulled tight by hand)
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Mech moved by hand to same position with shorter chain on
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Longer
Thanks All.
Now set to the longer" setting.
RD-R7000
Mount the chain on to the largest sprocket and the largest chainring. Next, add 1-3 links to set the length of the chain.
When mounting the chain, if the inner links and outer links match (as in [1]), set it to a length with 2 links added.If the inner links match together and the outer links match together (as in [2]), set it to a length with 1 or 3 links added.When setting to the length with 1 link added (in [2]), if you are concerned about drive wandering after mounting the chain on the largest sprocket and largest chainring, set it to a length with another 2 links added.(x)+2 links(y)+1 link(z)+3 links
I have always done big ring to big ring then ad 2 links including the quick link. I’ve never took notice of where the mech sits tbh and never had any bother