- Changing your gear cables could quite possibly be
the best thing that you can do to improve
the performance of your shifting.
Putting new, good quality cable inners and outers on
will improve the accuracy of your shifting.
It's gonna make your shifting action lighter.
And particularly, it's gonna help with
troublesome downshifts,
so going from the big ring to the little ring
or changing to harder gears at the cassette.
Now, doing it right, doing it by the book,
could make even more of a difference as well.
So this is how to do it.
As you can see, we are changing the gear cables
on a Shimano equipped bike,
and Shimano recommends you use their own cable
inners and outers.
So that is exactly what we are going to do.
In some cases, you may find you can just replace
the metal inner.
So, perhaps it's became damaged in some way.
But generally, you'll find that if your gear shifting
is becoming heavy, you need to replace both.
To do the job, the only specialist tool you need really
is a good quality set of cable cutters.
However, you may also find that a pick comes in handy,
as does a file.
And then, if you've got internal cable routing,
you will also need one of these, a thin plastic tube.
The first step is to remove your old cables.
So to do that, we need to loosen the Allen key cinch belt
on the derailleur, and it's the same
for either the front or the rear derailleur,
and then snip off this cable end cap,
so it's that little bit of metal there,
using your cable cutters.
Now, before we yank our old cable out.
We need to do one quick check,
and that's to see whether our cables our routed internally.
So, like this one, where they're hidden inside the frame.
'Cause if they are,
we then need to use a thin plastic tube.
What we wanna do is actually thread it
over the old cable, and then into the frame.
That way, when we start pulling the old cable out,
this plastic tube gets dragged all the way through
the frame, whereupon it can then act as a guide
for our new cable.
So you literally then just put the new cable
into this tube, and then reverse the process.
It can literally save you hours of poking around in the dark
inside your frame, which can happen on some bikes
which have poor internal cable routing.
Now, it will be a very good idea
to put a piece of tape over that plastic tube.
Keep it in place, because we really, really
don't wanna lose it.
Frustratingly, when we're replacing our cable outers as well
that does mean we have to unwind our bar tape.
However, if it's in good condition, like this,
and it's not stuck down,
then I tend to reuse it.
Slightly controversial, I know.
But, I think I can get away with it.
So, all you gotta do at that point
is to pull back the lever hoods,
and then unwind your bar tape as far as this point.
Saving time and money.
Now, don't just discard the cable outers
that you've taken off your bike
'cause we're gonna use these as templates.
And we'll just cut the new ones to right length.
In actual fact, now would be the perfect time
to do just that.
Hold the new cable next to the old one.
And then, where the old one finishes,
you wanna make a really nice firm cut
at 90 degrees.
Now even with the best cutter in the entire world,
you're quite likely to just have to squeeze the end
of the cable outer together just to make it round again.
And then, as you can see if you look closely,
the inner sheath there is just a little bit compressed.
And so at this point, we take our pick,
although probably the end of a biro will do the job,
and then just make it, the opening a little bit bigger
so the cable can pass as freely as possible.
You can always take a file, and then just file down
the end of the cable out there to make it super-flat.
'Cause that will have a small bearing
on the quality of your shifting.
Basically, the flatter that is,
the less chance there is for the outer to compress
or to flex against the cable ferrules.
In our dedicated pack from Shimano of inners and outers,
there is one length of cable outer
that's designed to be used between your rear derailleur
and the frame.
So it's important to use that bit in the right place.
And it's also important that you cut
the right end to length.
So not the bit that's got a silver ferrule on the end of it.
That's a ferrule, by the way.
It's that little bit that goes on the end.
Now the general rule of thumb with cutting
cable outers to the right length is that
they need to be as short as possible before
they start affecting either the quality of your shifting
or the ability of your bike to actually steer.
So, bends that are too tight in your cable outers
will load up the friction on the cables,
and so make your gears worse.
And then, you also won't be able to turn
your handlebars freely, of course,
without the cable outers being pulled from their stop.
Okay, let's start some re-cabling, shall we?
Now that set of cable inners and outers from Shimano
have everything we need.
So, two inners, enough outers to re-cable the bike,
and also all those crucial little cable ferrules.
Now before we thread the cable into the shifter,
we just need to make sure that it is in the hardest gear
at the back.
So you click all the way down using that lever.
And then if you're doing your front derailleur cable,
then you need to make sure the shifter is in
what would be the little chainring.
Then, you simply thread it in.
Now, different Shimano shifters thread cables
in different ways.
So this one here goes through from this side of the lever
and through to the other side.
Thread your first cable ferrule on.
Now these ones actually have a groove in
that fits inside the shifter better.
So there is a dedicated ferrule for this particular job.
Now you notice that I'm installing these cables
without adding any kind of grease or lube,
and that's because these Shimano ones have got
a special polymer coating on the inner
that makes them super duper slippery.
And then, they've got Shimano's own choice of grease
already inside these cable outers.
So, I don't need to do anything.
Makes life a little bit easier.
Now if I was installing lesser cables on my bike,
then I would choose to use a little bit of light grease.
Now, it does increase the friction ever so slightly
of your shifting, but where I ride,
it actually makes the whole system a little bit
more weatherproof.
So it just lasts that little bit longer.
Install a ferrule on the other end of the cable.
These ones have got really long nozzle on them, so
it improves weatherproofing.
And then, we can thread it
back into our frame.
Now once you have successfully got your inner cables
through your frame, you can now give yourself
a pat on the back.
By this point, if you were re-cabling your front derailleur,
then the cable would already be there.
Obviously, with the rear cable, you have one extra length
of housing to go.
So, you have one cable ferrule on the end.
Then you have your cable outer
with the metal ferrule that we talked about earlier
coming last.
Now with the inner cable threaded all the way through,
we now just need to loosely cinch in place
by tightening down that cable clamp bolt at the end there.
And then, at this point, I'm gonna refer
to two videos that are already on the channel,
'cause what we need to do next are index our gears.
So we have how to index your rear derailleur
and how to index your front derailleur.
But before you go to those videos,
then we also have one last job.
And that is we need to re-tape our handlebars.
And of course, securely tape our outer cables
under the handlebars before we do that.
Now even before indexing, we do need to, of course,
get rid of that extra length of cable
that's now flapping around outside our derailleur.
So cut it about 2cm away from the derailleur.
And then to finish it, we need to put this little bit
of metal, which is a cable end cap,
over the end of the cable,
and then we cinch it in place using the crimping section
of our cable cutters.
And then we are just ready to index our gears
and make them work perfectly.
Like I said, we've got two great videos
already on the channel.
So if you wanna get through to them,
how to index your rear derailleur down here,
and how to index your front derailleur down there.
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