- This is our GMBN Tech essential series,
where we look at varying components on the bike.
This week we're going to be focusing on the headset.
An often misunderstood or underappreciated part of our bike.
So we're going to look up the individual components
that make up our headsets,
as well as how to keep yours running smooth
and maintaining it.
(relaxed music)
Headsets are often overlooked when we talk about the spec
and componentory of on our bikes.
But a smooth, well-maintained headset
will not only run so much quieter,
but it will feel so much nicer through the handle bars.
Headsets come in varying shapes or sizes
but they all have the basic same essentials.
There are two different types of bearings
that we're going to be talking about today.
There is a third type
which I'm not going to into too much detail here,
which are basically what we call a threadless headset.
Which is like these ball bearings but without the cage.
Now on our sealed bearings they tend to be more robust.
They're better sealed from the elements.
They run smoother for longer.
But they also a stiffer interface.
So on your really hardwearing downhill bikes,
this would usually be the one to expect.
Each bearing comes with angles on the inner and outer race
and that's specified normally on the side.
And that's really important.
If you're running the incorrect angle,
your headset bearing will be floating around in there
and the interface won't be pairing up correctly.
Similarly on these cage bearings if they're over torqued,
they can cause excess wear
and pit the cone they're riding up against.
On modern frames you'll often find that these cups
are actually integrated into the frame.
Now this is a benefit in some ways.
It's lighter, it can also,
mean you can get your stack height lower.
But I still think that the old cup and cone headsets
still have a place.
Now some people find they can eek extra life out of bearings
by packing them with grease when they are worn.
That's not something I really subscribe to.
I think that if you put too much grease into a bearing,
what actually happens is the bulls stop rolling
and actually begin to slide.
Which yet again creates excess wear.
Now I think that when a bearing is worn, it's worn.
It's a consumable part.
It's like a chain or it's like brake pads.
I'm not somebody that kind of thinks they owe you anything.
I think when they're done, they're done.
You should just replace them.
And honestly you can sometimes make them feel so smooth
in the workshop,
but as soon as you put some preload through there,
you get out riding,
you'd be amazed what noises can come out.
And you can check for wear.
Often this inner race would have been at play this way
but you can really feel the front end
obviously with a steerer going through it,
it magnifies it quite a lot.
So if it's worn, it's worn.
Just replace it.
Don't hold any kwams.
So no matter what the headset
they will follow the same basic theory.
So this is your crown race
which sits just on top of the fork CSU there,
which is the Crown Steerer Unit.
And that's basically the angled interface.
Secure that bearing on the bottom.
From then, they slot into your cup
or the lower bottom of your headset and your frame,
just like so.
And that's all the headset is on the bottom half.
On your top half your headset,
it actually builds out symmetrically.
So we start with the cup which sits in the frame, bearings,
this one comes with a little seal.
And then you've got the inner interface there,
which slots on.
And an expanding wedge.
And then all basically follow the similar principle.
Sometimes all those units can come as one piece
but it all does the same job.
The last piece is your star fangled nut.
Now this sits in your steerer.
Now this bolt gets hammered down into the steerer
and although it can go down, it can't come back up.
So it makes it perfect for applying preload.
Which you do via this bolt in the top cup.
Now what we're going to do is,
we're actually going to set up the headset on this bike
and hopefully be able to provide some insight
for how it all works.
So I've removed the front wheel.
I've taken off the brake.
I'm going to release these pinch bolts
and take off the tension and get the folk out of the frame.
So here we have my folks removed from the bike
and all of the headset componentory taken off.
Now on the bottom, you can see the crown race.
Which as you can see is an angled surface.
So in this bike, like most modern mountain bikes,
uses a sealed bearing system.
Like I said earlier on this aids with not only
sealing the elements out but also stiffness.
So if you ever need to remove your crown race,
you have got the option to slot a screwdriver in there
and twist and it'll pop up.
Alternatively, you can slot a screwdriver in the back there
and gently push it up.
Now you want to be careful of that
because you often see people with these horrible
marked forks where they've been just hammering at it
and it looks kind of a bit, not that nice.
So try and stay away from it.
Now what we're going to do is we're just going to stack
each component of our headset together.
Now there's kind of an (sigh) varying
different schools of thought
when it comes to greasing your headset
and how much you should apply.
Now what I'm going to do is put a nice light skimming of grease
on all the components, all the bearing interfaces.
Now this will stop water corrosion whilst not accumulating
loads of dirt.
Sometimes you can get dirt trapped in the headset
and the creaking you hear
are those grains of dirt being crushed over and over again.
So we're going to go for hopefully a happy medium
and just put a nice skimming on there.
That crown race is now nicely covered in grease.
Like I said not too much
and we're just going to slot that bearing on top.
After, make sure this interface is nice and clean,
in the headset cup there.
I'm just going to put an equal amount, a nice skimming,
nothing too crazy.
Once your folk is slotted into the frame,
often you can quite simply run out of hands.
SO what I like to do,
just run a toe strap through the frame,
underneath the fork,
like so just to secure it in place.
So we have our upper bearing here.
See again with the interface on the outside on the bottom.
And then inside on the top,
just going to get a little bit of grease,
just skim it on there and just drop it over.
It might take a little bit of wiggling
but it should snap in.
And those nowadays are made to a really nice tolerance fit.
The next part of the headset is this wedge here.
Which is a bit bearing interface as well don't forget.
Let's make a sort of also just a nice skimming,
that can also click in.
Now some headsets come with these secondary plastic seals.
Which do just slot on over
just to give the bearing any extra protection really,
against dirt coming in from the outside.
Then comes the last piece of our assembly.
Which just slots over just there.
You can't be quite finicky with that one,
and make sure you get your branding all nice and lined up.
Next we have our headset spacers.
Now these are really important part.
And I'm going to show you why.
Now it's a very crude demonstration,
I've removed too many spacers here.
So as you can imagine, no matter how much I do up this bolt
and it pressurizes the system,
it's never going to remove that play there.
So when we put the correct amount of spaces back on
this top cap and bolt flushed in
just the preloaded the system.
And what that's going to do,
it's actually gone pull the steerer up
to add tension to the system.
Whilst this is really important that
it leaves a gap between the top cap
and the top of the steerer.
So if your folk is sitting flush or even proud
of that top spacer, you're not going to get your headset tight.
It's for this reason that having a spacer sit above the stem
is always a good idea.
It actually makes sure that not only does your stem have
maximum contact with the steerer,
but there's no embarrassment, egg on face moments,
when you develop play mid ride
because they wasn't enough tension in the system.
So now the system is nicely kind of torqued up,
just enough to remove play.
You really don't want to be over tightening that.
If you using the spanner down here,
you've probably gone a bit wrong.
It's also a good opportunity,
now is the time to get your top cap ? Aligned.
That one is important and I don't care what you say.
And for me I'll always put in the little safety
of just twisting my handle bars because then I know
these tops, these bolts aren't done up.
So I've put my front wheel back on and reconnected my brake.
Now as you remember I had my handle bars
deliberately off center just as a reminder.
So what I'm going to do is just stand over the bike.
Once I get them vaguely straight
then we're just going to make sure that is nipped up
while straightening the handle bars,
haven't taken any torque off or added an extra one.
And a good tip with straightening your front wheel
is don't do it off the stem and the wheel this way.
Do it off the crown of your folk
and your handle bars that way
and you'll get them nice and straight.
Even a donut like me can do it.
With the stem bolts, with any pinch bolts really,
it's really important you only tighten the bolt
until it's no longer the loser of the two bolts.
So you just go one two.
Yet again, please don't be hanging off the allen key.
You really don't need to be.
Then I'll be, she's all ready to go.
Look at that.
So that was the GMBN Tech essentials on headset maintenance.
Now if that has just merely wetted your appetite ,
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