I am replacing the chain on my road bike soon. How do I know how many links to get? Does it have to exactly 114 or 116. Or is it not a big deal?
I ordered a 116 link chain. Will I need to shorten it?
Thank you.
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Sign up to join this communityI am replacing the chain on my road bike soon. How do I know how many links to get? Does it have to exactly 114 or 116. Or is it not a big deal?
I ordered a 116 link chain. Will I need to shorten it?
Thank you.
If your old chain was 114 links (assuming it was the right size to begin with) then it's a good idea to take a couple of links out of it. It'll still work with two extra links but shifting may not be optimal and the chain will fall off more easily. Keep in mind that one chain link is composed of an inner and outer link, so a link is actually two pieces with a hinge in the center. This means that to remove two links, you'll actually remove four pieces of chain with three hinge points.
If the old chain was 116 links and you're trying to replace it with a 114 link chain, you'll run into problems. A chain that is too short can jam when shifting and puts puts too much strain on your rear derailleur.
To determine the correct length, wrap your chain around largest chain ring in the front and the largest rear sprocket, without running it through the derailleurs. Make sure that the chain is long enough for one full link (again, inner and outer) to overlap and you'll probably be spot on.
You can read more about it here: http://sheldonbrown.com/derailer-adjustment.html#chain
A standard replacement chain is always several inches longer than needed for a standard non-recumbent, non-tandem bike. What I generally do is hang both from a wire and match up the links (the old chain will be "stretched", so you can't simply match by length). Then I "break" the new chain at the location (number of links) that matches the old.
Skilled mechanics can simply stretch the chain around the big rings front and rear, put their finger on the link that meets the other end, and break it there, but I'd rather be sure that my new chain matches the old exactly (if the old performed well).
I am writing a summary answer. It does not contain new info, but I would have benefited from having it as such, so I expect it might be useful for others as well.
How do I know how many links to get?
To be completely sure, you would count the number of links in your current chain, assuming it is ok.
Nevertheless, that is almost never needed.
Chains sold are usually longer than whatever is needed.
I have to change now a chain with 106 links, and the shortest chain sold has typically 114 links.
Does it have to exactly 114 or 116. Or is it not a big deal?
As per answer above, it is not a big deal.
Will I need to shorten it?
Most likely, yes.
How? See the cited link from Sheldon Brown.