To keep your bike in good working order, it's important
that you service it from time to time.
In the same way, that you service your car.
And one of the most important areas to keep on top of
is your drivetrain.
Particularly, if you have a triathlon coming up.
Leave that dirty or in bad working order,
and you could be wasting valuable watts, and energy.
So today, I'm going to be using my bike,
as an example, because it's rather dirty,
and I'm going to show you how to prep,
and clean your drivetrain, ready for race day.
Well firstly, it's probably worth us explaining
exactly what a drivetrain is.
And it is essentially, all these moving parts here,
that help to move the bike along.
We've got our cranks, our chainrings, our bottom bracket,
our chain, and our derailleurs.
And this is a really important area of the bike because,
as you ride your bike and you change between the gears,
these components and parts all pull and rub on each other.
And without a lubricant between them,
you've essentially got metal on metal,
which is not what you want.
And, throw in grit and dirt with that, you've got
horribly, gritty and rough drivetrain which is
only gonna deteriorate those parts and components.
So, that's where the lubricant comes in.
But that will wash away and wear away over time,
so it's important you stay on top of
lubricating these parts.
But we'll get into that later.
For now, let's talk about the servicing.
Because, there is no point in going to all the effort of
cleaning the parts if they're well past their best
and maybe need replacing anyway.
And one of the most common parts of the drivetrain
to be replaced and to wear out is our chain.
And one of the easiest ways of measuring chain wear
is with a chain checker tool, like this one.
Now, this one has a series of numbers on it.
We've got zero, 0.25, 0.5, 0.75 and 1.0.
And that is basically the percentage of
elongation between the links.
So anything up to 0.5 and
you can keep using that chain, it's okay.
Anything above 0.5, and
yeah that chain is past
its best and you probably want to replace it.
Now this works by inserting the two pins underneath,
in between the chain links.
And, we're starting on zero, and we're gonna push this
black dial until those pins can't push
against the links any more.
Now remove that, and actually,
my chain is past its best.
We're sitting, more or less on 0.75.
But if you don't have a chain checker tool
you can always just use a ruler.
And we're gonna use 12 inches as our guide on this.
And we're gonna count 12 chain links, and that includes
one outer and one inner.
And, if we line up the zero with one of the chain links,
and the 12 inch mark should then line up with
the rivet at the end.
But as I've shown already, my chain is slightly elongated.
And then if you just want to do a quick and rough check
without any tools, then you want to whack your chain
in the big ring, and then, we're going to look at the
three o'clock position on the chainring,
and you're just going to grab the chain,
and try to pull it off.
Now, a good and new chain, you'll be
barely able to pull it off and won't be able to see much
daylight between the chain and the chainring.
But for a worn out chain, then you're gonna
start to see some daylight, and you may even be able
to pull it almost away from one of the teeth.
And if it is elongated past that recommended point,
then it's actually advised that you change the chain
and the cassette at the same time.
Now it might sound odd for me to replace the cassette,
and the chain, but they both wear into
each other over use.
So, you can actually get away with just replacing the chain,
but if you find that the chain starts slipping,
it's not changing gear very well, or just making
a lot of noise, then that may well be the issue,
may well need to replace that cassette.
Which is another good reason not to leave this
until the night before the race.
Make sure you change it well in advance,
and then you can find out whether it works,
and it's all okay to go.
And if that's all okay, then it's time to start cleaning.
We're gonna start the back of the drivetrain,
and on the cassette.
Now you can fully remove the cassette as I've shown
in a previous video, and then fully soak that cassette.
Or you can quite thoroughly clean it whilst
it's still installed on the wheel.
So we're gonna take a look at that easier option and
for that, head outside.
We're going to start spraying a bit of
degreaser onto that cassette.
Now avoid the urge to start scrubbing at it straight away.
You want to allow it a little bit of time to work its magic,
and start breaking that dirt and grime down.
And then, after a minute or so, grab your brush,
like this one, from Park Tool,
and start working in between the cogs.
And then, if you've got a brush like this,
flip it around and use the serrated edge, to then,
slot in between the cogs, and start working out
any of those big clumps of that stuff in there.
So you can repeat that process over and over
until you're happy the cassette is sparkly and clean.
And obviously, we are gonna wash it, but we'll get
back to that in a minute.
For now, we're gonna move on to the derailleur jockey wheels
which are these two cogs, here and here.
And, given that their job is to shunt a greasy chain
up and down the cassette, and the chainring,
they have a tough old life, and it's amazing actually
how much dirt can build up there,
and actually how much resistance that causes.
Which, certainly isn't something you want before race day.
To start with, just spray a little bit of degreaser
onto those cogs.
And then use a brush, or an old rag,
to wipe off that dirt.
But if that doesn't work, you can use
a flat headed screwdriver, just lightly
against the jockey wheel, just to try and
pry any of that old dirt off the jockey wheel,
and then just finish off by wiping it off with a rag.
And now that the jockey wheels are clean, and exposed,
it's time to check their condition.
So, they should have a flat, blunt profile to them.
But over time and over use, they'll start to form a
sharp, tooth-like profile.
When they do get that point, it's time to replace them.
Fortunately for me, mine are fine.
And now, we need to clean that degreaser
off the cassette, and off the derailleur.
So now that it's all clean, let's head back inside,
and take a look at the chain.
It's made up of a number of intricate parts,
that ideally you want to be soaking to get thoroughly clean
and running smoothly.
Now I was a little bit late to the party on this.
But these chain scrubbing devices are
an absolute game changer for that.
You just want to just remove the rear wheel
and then attach the chain cleaner to the bottom section of
the chain, and make sure the chain is nicely slotted in
between the brushes.
And then just fill the chain cleaner up with
a chain cleaning solvent like this one,
and you just fill it up through
this hole here, and then fill the bottom half of the
chamber up to the fill line,
and then rotate the pedals backwards
for 30 revolutions.
And maybe it's just me, but it's quite satisfying
to see the fluid in the bottom half of the chamber
just getting darker and darker.
But when that's done, remove the chain cleaner,
pour away the fluid,
and now you want to replace that with some
soapy fluid in the bottom half of the chamber.
Repeat the process, and then again,
remove the chain cleaner, and now
just grab a dry and clean rag
and wipe the chain down.
And whilst we let the chain dry off,
we may as well tend to the chainrings.
Now, similarly to the cassette, they do wear with time
and they follow a relatively similar path, so,
over time you might start to notice a slipping
or a slight spongy feel.
If you do, then you want to replace the chainrings.
But for now for cleaning the chainrings, you want to
remove the chain and place it on
the frame side if possible.
It's just to get it out of the way,
so then you've got better access to the
chainrings to clean them.
And by now, the chainrings will have had their
fair share of degreaser working on them that's come
off the chain whilst we were cleaning that.
So you're ready to start brushing them or,
if you just need to, just use a rag.
Now, one area that you really want to focus on
is in between the chainrings.
Quite a lot of grit and dirt builds up there.
And then when you're done with that just use a nice
clean rag, and just wipe it down.
And by now, hopefully, the chain is dry,
and you're ready to apply some chain lubricant.
And you want to apply that to each rivet
through the chain.
Allow it some time to seep into the chain,
and then use your rag to wipe off any excess.
Once that's done, you want to work
your rear wheel back in.
And that is your slick race machine ready to go.
And if you'd like to see more videos like this from GTN,
just click on the globe, and subscribe.
And if you'd like to get hold of some of this
GTN kit just head on over to our shop.
And if you'd like to see that video I mentioned earlier
about how to remove your cassette from your bike,
just click over here, and if you'd like to see how to choose
tyre pressure for a triathlon, just click over here.