Doddy: From time to time, you will need to
adjust the derailleur gears on your bike,
and it can sound a bit tricky if you don't
know what you're doing, but actually, once
you understand the basics of the hardware
itself, it's very easy and something that
anyone can do at home. So in today's video,
we're going do this with a SRAM derailleur,
but fear not, if you have a Shimano one on
your bike, we've already made that video so
you can check that one out in the description
underneath.
[music]
Okay, so before we get started making any
adjustments to this bike whatsoever, let's
just take you through what the SRAM derailleurs
look like. The function and the form is exactly
the same really as most other derailleurs
on the market, but they do have a few small
features to set them aside. The basics look
pretty similar to anything else. You have
a lower cage unit known as the lower cage
and it has two wheels on there. These could
be called guide wheels or jockey wheels and
sometimes pulleys. They rotate on little bearings
and the responsibility of this cage is basically
to take up the slack in the chain when you're
in a higher gear.
A higher gear means smaller sprockets, so
there's a bit of an abundance of chain and
that is sprung to take up that slack. Accordingly,
when you go into a lower gear which means
using more chain, it goes the opposite way
to accommodate for that. This lower cage is
heavily sprung and it actually has a clutch
design. Unlike the Shimano one you can turn
on and off, the SRAM one you can't turn on
and off, but it does have a locking feature,
which means it's really easy to adjust and
also means it's super easy to remove your
rear wheel. It's a genius feature and it's
exclusive to SRAM. We'll show you how to work
that a bit later in the video.
As far as shifting goes, it has the same parallelogram
style design as you've seen on most derailleurs.
This correlates to when you're doing the clicks
with your shifter, it will move across and
enable the chain to derail from sprocket to
sprocket. Then there's three main adjustments
and a cable clamp. Cable clamp obviously just
clamps that cable that you're operating at
the shifter end, and the three adjustments,
two of them are your limits for smaller sprocket
and your largest sprocket just to make sure
the derailleur can limit the movement that
it has, and the other one is the B tension,
also known as the B screw.
This one is responsible for the height of
these guide wheels in relation to that cassette.
You need to have this sprocket correctly adjusted
for clean shifting. We're going to show you
exactly how to do it, it's dead simple.
[music]
Okay, so firstly, let's have a bit of a system
reset to make sure everything is ready before
you can make any adjustments. Let's go up
to the shifter first. This is the barrel adjuster.
Its job is to take up any slack in the system.
You can sometimes hear this referred to as
cable stretch, but it's not technically cable
stretch because the metal cable doesn't stretch,
but you do get slack in the system as the
outer housing and the sheets and stuff can
bed into place so you get small amounts of
movement in that system. It's a simple screw-ins
barrel basically and it compensates for that
slack. I want you to screw it back into the
shifter, basically giving it more slack.
You might find the outer housing here moves
around a bit. Just have a quick double-check,
make sure everything feels smooth. Does the
shifter feel smooth? If it doesn't, give it
a bit of spray lube on the inside there. You
might need to replace the inner cable itself.
If that's something you do need to do, before
you go any further, check the video out that's
in the description underneath this one and
it shows you how to replace the cable on a
derailleur and also deals with a little bit
of generic information about indexing your
gears, but we will cover that with this particular
video. Have a bit of a sense check when you're
up at the front end here.
Make sure the cables and the hoses are all
long enough that your steering is not constricted
and none of them are pulling on anything.
If any of those hoses are being crimped, or
kinked around adversely, or they're being
pulled on, that will hamper your gear shifting
and your brakes and other things on the bike,
so just do a sense check and make sure everything
is operating smoothly. Just before we get
onto the actual derailleur itself, just have
a quick sense check around your transmission.
Make sure that the actual cranks rotate freely
as they should do and make sure that there's
no stiff links or any obvious damage to your
chambering, your chain, or your wrist sprockets,
which is also known as the cassette.
Assuming this is all good, let's get started.
[music]
First things first is to make sure that the
derailleur is aligned correctly. Get yourself
in a position, maybe on a stool or something
similar, low down, and get behind the bike.
If you've got massive tires on your bike,
this actually can be quite hard and it might
be easy, for example, if you've got a fat
bike or you've got plus-size tires. To actually
remove the rear tire from the bike, you'll
need the wheel in there, of course, to make
this adjustment because that's where your
gears are situated. However, on this bike,
I can just about see, so we're going to make
do with this. I'm using a line of sight.
I'm looking at the derailleur, I want to make
sure that the derailleur itself, it hangs
completely vertically underneath that small
sprocket. It's really important that it's
nice and straight here. Do note that if your
derailleur is an old one, it's been bashed
a few times, the lower cage could be a bit
bent, so just pay attention there. Also, pay
attention to the hanger that the derailer
bolts to on the bike that could also be bent.
If any of those things is a bit of a problem,
you will need to tackle that at this point
because you won't get clean shifting if it's
not aligned, it's that simple. To make that
sort of adjustment, there's a few specific
tools, but you can get away with using an
adjustable spanner.
If you want to see me using this adjustable
spanner to do exactly that, the video where
I fix up an old shed bike essentially is in
the description underneath. That was really
bent and the derailleur itself was bent and
I manipulated it by hand and got it working
perfectly. You can check that video out and
it gives you some other tips on doing ups
and knackered components as well. Just because
they're knackered, it doesn't mean you can't
keep using them. Anyway, I digress, back onto
this. We're looking at the derailleur, it's
hanging and is hanging straight underneath
that bottom sprocket, but we want to check
that it's correctly aligned as well and this
is where your limit screws come in.
Note there's two screws here. Depending on
the model year of your particular derailleur,
it might have a crosshead screw there or like
this one, it might have an Allen key. In which
case, it's a three-millimeter. There's two
screws here. One correlates to the lower gears
which is your biggest sprocket and one correlates
to the higher gear, which we want to adjust
which is the smaller sprocket. Note here,
as I adjust it, you can see that sprocket
moving around. You want to get it into it,
directly underneath that smallest sprocket.
Make sure you move around a little bit to
get the best vantage point because you want
to be completely in line.
This is why I said the tire can get in the
way here. If the tire is a problem, it might
serve you to get rid of the tire to make this
process an easier one.
[music]
If you're struggling to make this adjustment
and you're finding the derailleur is not reacting
enough, there might still be too much cable
tension on the system. In which case, you
want to undo or loosen the cable clamp. Again,
depending on the terrain, this could be a
four-millimeter. If it's really old, it could
be a five-millimeter. On this case, I need
a Torx T225 in here. I'm just going to loosen
this off and see the cable and now is nothing
to do with it, so there's no cable tension
affecting the derailer. If you do this, you
might find when you undo the bolt, the derailleur
naturally just moves a fraction. It might
just be a couple of millimeters.
In which case, you found the first bit of
the problem. Return to make an adjustment
on the lower part here until the derailleur
is completely in line. You can just check
that the derailleur functions freely by cycling
the bike through the gears and manually manipulating
the derailleur. Be careful where you put your
hand, but you can use your thumb on the parallelogram
to just push the derailer through a few of
the gears as you're cycling through using
your hand on the pedal. Take your time with
this and you'll get an idea. You'll be able
to see if the chain is naturally going to
drop back down again.
When you release your hand from there, the
derailleur should just allow the chain to
pop back down onto that smaller sprocket.
If that is good, then now's the time to put
that cable tension back on now. It's really
important to say, when you're pulling the
inner cable through the system here, you don't
want to be pulling it tight because if the
derailleur have such a small amount of cable
pull to operate them or actuate them, you
can mess things up here, so you want to pull
the cable till it's taut. I recommend using
something like, say, a needlenose pliers because
it makes it really easy to grip and they're
really precise.
You can use regular pliers, they're not quite
as accurate though. Give the cable a bit of
a pull just to make sure everything is in
place on the bike. If your cable is externally
rooted, you can check the stops just to make
sure that the cable housing is sitting into
the stops correctly and nothing's going to
give a bit later on. Give the cable a good
hard pull, and then you want to gently follow
that cable routing around. Be sure to make
sure you follow the correct cable routing.
It's very slightly different on all derailleurs,
but it is generally very obvious. Note how
this one follows around here with the housing
enters its derailleur, and you can see a little
groove that the cable sits into.
We need to just pull it taut, and then tighten
up with a pinch bolt there making sure that
the cable is correctly clamped. With any luck
if you've got this right, the derailleur won't
have actually moved, it will have secured
that cable. The first part of indexing your
gears here is to see if the derailleur jumps
up with one click at the shifter. The aim
here is one click per gear. This is known
as the indexing of your gears. Try this by
cycling the bike along with your hand on the
pedal and just changing gears at the shifter.
This makes sense if you've got your bike in
a work stand, if you haven't, you might need
a friend to help you here, but honestly, a
work stand is the best friend for this.
It's a third hand essentially and so useful
for many other jobs. Cycle through one click
of the shifter and it should hopefully correlate
to the derailleur jumping up one gear. If
it's not quite managing to jump up, then you
need to apply a bit of tension using the barrel
adjuster back at the shifter because that
means there's a little bit of slack in the
system somewhere, you need to compensate for
that. Hopefully, if you've pulled the cable
taut enough, you might just need to add quarter
or half a turn or maybe a full turn. Make
the adjustment and try again until the chain
jumps up cleanly onto that sprocket, and then
select it so you can jump back down again.
If you can get that one gear nice and smooth,
you're doing well. Next up is to make sure
this works correctly for the first four gears
or so. Pretty much, once you've got those
four gears working smoothly going up and down,
it's going to work perfectly the whole way
up, but there's still some more adjustments
to make a bit later. If your chain was actually
over-shifting and going up too much, there
was too much tension in the system. This means
you've actually pulled too much cable through.
You pulled it tight, not taut like I said.
In which case, you need to reduce that again.
Back to the clamp again, release that cable,
and then pull it taut.
Remember taut, not tight, that is the key
to getting correct shifting. Back to square
one again, shift it one gear until you get
it to clean four gears up and down and it's
working nicely between them. It's time to
move on to making your lower adjustment. Lower
correlates to the lower gear which is the
biggest sprocket. That is the one at the spokes
side of your wheel. This one is a crucial
one to make because if it's not right, you
might not get into that gear to start with,
which is annoying because you won't be able
to climb up those really steep climbs and
use your full range of gears, but worse, if
you over-shift, there's a chance your chain
can get caught between the back of the cassette
and the spokes.
This can snap your chain, it can damage your
wheel, and it can be a real pain to get out
again, so make sure you get this one right.
The same thing applies, get the bike up into
that gear. Just take caution in case it over-shifts
and then using your line of sight, this is
where it's really quite difficult if you have
a big tire especially in this combo because
you're so far inboard of the wheel, and that's
almost directly in line with the rim, so it
can be very tricky at this point. Again, if
you're struggling here, you will need to make
sure the tire is not on the bike.
Continue making adjustments to that limit
screw until the upper of those wheels is sat
directly underneath completely in line with
that biggest sprocket on your rear cassette.
Before you start playing with the gears, there's
one final adjustment you need to make sure
of and this is a perfect time to do it because
you make the adjustment only in this gear,
in your biggest or your lowest gear. This
is called B tension. There's a B tension screw,
this is it, also known as the B screw. The
responsibility of this is to make sure the
derailleur is at the correct height in relation
to that cassette.
It adjusts when you look carefully, I'll just
make an adjustment here and you can see the
top wheel moving up and down slightly in relation
to the cassette. This is a really important
adjustment to make because it can make the
difference between your gears shifting smoothly
or everything just not working quite right.
Despite everything else being exactly right,
this can really affect everything. You want
to have 15 millimeters of daylight between
the biggest sprocket and this wheel when you
are sat on your bike.
That is if you have a suspension bike it needs
to be sacked, so trying to get this can be
quite difficult and it ends up actually being
about four or five millimeters when you're
not on the bike like this one is in the stand.
Thankfully, SRAM make this little gizmo. They
make this for the Eagle like I have on here
which is 12 speed, but they also make it for
11 speed and other derailleurs, so it's a
really good tool to have. If you manage to
buy your bike, if you bought your bike new,
it's probably got one of these in with the
manuals. If you bought the derailleur new,
it will come with one of these.
If you haven't got one and it costs a couple
of quid, it's well worth getting one from
your local bike shop or just ordering one
online if you can't source one if you're not
near a bike shop. All you do is hook this
around the upper jockey wheel there and basically
correlate the sprockets to this, and then
basically make your adjustment with the B
screw until this is dead in line and you'll
have perfect shifting. The name of the game
here really is to get that upper wheel as
close as you can to the biggest sprocket without
fouling on it. The closer it is, the cleaner
shifting you'll get coming back down that
cassette into your higher gears.
If it's too far away, it will really struggle
basically, so make sure you get that adjustment
just right. With the B screw adjusted correctly,
you can now check if your gear indexing works
correctly because you still might need to
make a fraction of adjustment to that upper
limit for that big lower sprocket there. Run
back down the gears and it should correlate
to one-click per gear. Is it working? Brilliant.
If it's not hopping up or it's not going down,
you will need to make just a bit of a fine
adjustment to that limit. In which case, the
job's a good done. There you go, so we've
made most of the adjustments the derailleur
to make sure it works and KO indexing working.
There two more things to go into.
One is the constant adjustment you'll need
to make, we'll get to that in a sec, and the
other one is the cage lock, which we haven't
covered yet. The cage lock is a little button
here and it basically protrudes out the back
and it locks the cage in place. This makes
it dead easy to remove the wheel from the
bike. You'd simply rotate the cage forward,
press the button, and you see you will hold
the cage completely locked out. A genius feature.
If you are struggling to make that adjustment
on the smallest sprocket at the back, you
can lock the cage out and it can actually
give you a slightly more clean line of sight.
If something's bent, this will expose it,
so that's a good one to go back to if you
have been struggling. The last thing to say
is about the constant adjustment. With any
set of gears, whether you're using a new cable
or even an old system like this one that I
have just made some adjustments to, there'll
be a settling in period. People will tell
you this is where your cable stretches, it's
not. This is where the cables, the outer cables
that is settle into the sheath, into the housing,
into the ferals, into parts of the frame.
As you move around on the bike, you go through
the suspension, everything creaks and moves
around.
As this naturally happens, there will be some
slack that's created and you'll need to compensate
by just dialing in that barrel adjuster. You
can do that, instead of wasting time doing
it in the stand, you can go for a ride, go
through all those gears, make sure everything's
working as nicely as you hope. You'll probably
find after a first proper ride, maybe two
or three rides that you might have a slight
delay shifting up from the bottom sprocket
into the first one up. You might just need
half-turn or a quarter of a turn just to add
a bit more tension on the system. Really that's
about it. It's a very simple system.
There were some cable tension and just some
limit screws essentially, dead simple. I love
cable gears. Hopefully, this video has been
useful for you. Again, it's just a specialist
video for those needing to adjust a SRAM derailleur.
We've got the one for the Shimano derailleur
in the comments underneath, and it might be
floating around over there somewhere or over
there. There's also the one on the shed biker
where I fix up an old bike. It's a great video
to watch, it might inspire you to do the old
bike in the garage or the loft, make a few
quid from it, give it to a friend, give it
to a charity.
It's a good thing to do and it'll help you
understand working on bikes a bit more. Can't
be a bad thing. Any suggestions for videos,
don't forget to let us know, best known as
comments. Thanks for watching.
