If your gears are jumping, or they're just not shifting smoothly and as quickly as
you think they should, then you probably just need to adjust them.
So, here's GCN's Guide on how to index your gears, and it should work for
Campagnolo, Shimano, and SRAM gears. So how does indexing actually work? Well,
your shifter pulls a set amounts of cable for each click, and that cable pull then
moves the derailleur a corresponding amount, which just so happens to be the
exact distance between the cogs. It's a simple system but it works brilliantly.
Now, if your derailleur doesn't sit exactly beneath each cog in
turn when you're changing gear, then the gears are not indexed, which is at which
point that they're going to be working badly. And It's the process of indexing to
correct that and to move the derailleur into the right place. You can micro adjust
it very simply by turning this little dial here which is called the barrel
adjuster. And that effectively makes the cable tighter or looser and therefore,
moves the derailleur a small amount. So at the moment, the gears are indexed,
but you can hear as I just move it half a turn, three quarters of a turn,
full turn. There you go, so, we have shifted it, you can see then that the
cable is moving. So, that's the principle of it. To index them is really straight
forward. So if your gears aren't working smoothly, then it could well be the
indexing that's the problem. So here is how to adjust it. And if you're setting up
your derailleur from scratch, then we've a video explaining exactly how to do that.
You can click on the link just over there. Before we get started with indexing,
even if your gears have been set up before, there's one check you should
always make, and that is for the limiter screws. So, those are these two here,
and they limit how far the derailleur can move either outwards,
so essentially stopping your chain from falling off this side of the cassette, or
inwards, essentially stopping your chain falling off that
side of the cassette, and into the spokes. So,
very simply move the derailleur by hand, then touch the shifter, and then
you can see whether or not the derailleur is directly underneath the biggest
sprocket and then at the back there directly underneath that one.
And if it's not, it's simply a case of adjusting these limiter screws here.
So, if you turn in clockwise, this is the high limiter screw, so that's the smallest
cog there. And you can see the derailleur is moving simply by being delimited.
Now to actually index the gears, it's worth bearing in mind that all indexing is
done using that barrel adjuster there. So, once the limit screws are set,
we'll leave them be. So, everything now is just going to be here.
Okay so, we need to be in the smallest sprocket at the back still, and then also
stick it in your little ring as well. We'll index it whilst the chain is on the
little ring, and then we'll check all the gears to make sure they're still working
perfectly when it's on the big ring. If there's any discrepancy between it might
mean there's an issue with alignment, but we'll check on that later on.
Okay, so, now, to get started, shift up one click. And you can see that nothing's
happening, it's just making a rocket, so start turning the barrel adjuster
anti-clockwise until the chain moves onto the next sprocket. Now, it's
still not going to be indexed perfectly there, but try moving it into the next
biggest sprocket, and then turn the barrel adjuster until it moves into that one.
And then change down and repeat the process. Still not quite there,
so more tension, another anti-clockwise quarter turn, and you can see that in
those three sprockets, it's not working, so let's try the rest of them.
That looks pretty good. It is essentially as
simple as that. Let's try the big ring as well.
Cool, so, remember that if the chain
isn't shifting properly going up the cassette going to easier lower gears,
then you need to screw the barrel adjuster anti-clockwise to make the cable tighter.
And if it's slow to go back down the cassette to into higher gears,
then you unscrew it clockwise to decrease the tension and then move the chain back
that way. Sometimes it doesn't quite go as easily as that, so if you're struggling to
index your gears, here are four tips that might help you. Now, first of all,
if you can index it going up the cassette going to easier lower gears, but you're
struggling indexing it coming back down, it's highly likely that it's down to your
cables. So, when a cable gets worn, and it's old, this gets loads and loads of
friction in the system. Too much friction, in fact, for the little spring in that
derailleur to overcome, so the derailleur struggles to move the chain back down onto
smaller cogs. So, in that instance, it's then just a case of replacing the cables,
but we've got a video showing you how to do that. And you can click on the link
just over there. Now, second thing, if you're going to index your gears on the
work stand but then when you get on the road, your gears are jumping around all
over the place, then it's highly likely that it's probably down to a chain in your
cassette being worn. So in that case, you probably need to replace either or both of
those, which is a little bit more expensive, but it's worthwhile.
The third thing to check is your wheel. Now, make sure that the wheel is aligned
in the frame properly. That's quite a simple mistake to make, but then the other
thing is if you just changed wheels recently, you might have to re-index your
gears, particularly if it's a different manufacturer. So obviously,
you rely completely on the position of the cassette
here. And if you change wheels and the cassette is in a
slightly different place, then it's going to put your indexing out.
The final thing to check and actually, it crops up quite regularly, is the alignment
of the rear derailleur. So, have a look from behind and make sure the derailleur
is sitting straight. You can do it by eye, but the best thing to do
is probably to head into your local bike shop, who will, in all
likelihood, have a tool like this which checks the alignment for you. So, that's
your gears indexed. Remember that to index and use the barrel adjuster at the back,
turn it anti-clockwise to move the derailleur, ever so slightly, inboard and
clockwise to move the derailleur outward. If it's not working, you need to check
firstly your cables to make sure that they're running smoothly. Then if it's
jumping around after you go out of the work stand, you probably need to look at
your chain or your cassette for wear. Also, remember that if you're swapping
wheels, then that might move your indexing in and out of line. And then finally,
check the alignment of your rear derailleur and correspondingly the mech
hanger as well. If you'd like a more thorough look on just how to set up your
rear derailleur, click on that video up there. And if you don't know how to change
a chain, then click on that video just there. And remember that to subscribe to
GCN, all you've got to do is click on me.