- Fixing a new fork to your bike is a fantastic upgrade,
and it can really improve the handling.
It's actually a fairly simple process
to do yourself at home.
So I'm gonna demonstrate by fitting a new RockShox fork
to my Nukeproof Scout.
Really simple, this is how.
(dramatic booming)
As with any job, working on your bike,
you're gonna need some sort of tooling to do this.
Now, if you're in a bike shop,
there's a lot of specialists tools
such as this crown race puller that you would actually need
to do this job on a bike but fear not,
there's plenty of alternative ways.
And although the correct tool is always the best tool
for the job,
you can actually do this with a very basic tool set.
So you're gonna need some sort of Allen keys
to remove the current forks from your bike.
You're gonna need a hacksaw or a pipe cutter,
some way of cutting the steerer tube down,
and you're gonna need a file.
And, of course, the all important tape measure
so you can actually cut the correct length
of your steerer tube.
So this is how you do it.
(bike wheel spinning)
So first things first,
you need to remove your existing fork from your bike.
So obviously putting your bike in a work stand
is the easiest and best way to do this.
If you haven't got a work stand,
then you definitely really do need someone to help you
with this task by holding the front end of the bike up.
So obviously you're gonna need to take the wheel off first,
because that's just gonna hinder things.
Take your front axle or your quick release
out of the bike there.
Put your wheel aside for later.
You won't be needing it until the end of the job.
Then next up, you wanna make sure
you remove the brake caliper itself
and the cable routing off your existing fork,
and let that just dangle down.
Obviously, you wanna make sure it doesn't hit anything.
Next up is to just release the actual cable guide
on the fork itself until that comes off the fork there,
and just remove it.
Make sure you don't lose the little bolt.
So, I'm actually gonna put that back on the fork
so I don't lose that.
Now moving on up to the stem there.
You're gonna loosen off your stem clamp bolts,
but don't remove the top cap just yet
'cause that will, if you have that off at this stage,
the fork could slide out onto the floor
and you lose all your headset gubbins.
So just loosen off the clamp bolts on either side there.
This particular one is four millimeter Allen key bolts,
but it's quite often a five and sometimes even a six.
Right, so they are ready to come out now.
Now this is the bit you need to pay attention for.
So I'm gonna slowly undo this top cap now,
and hold the fork at the same time so it can't go anywhere.
I'm just gonna remove the top cap.
Take note that the steerer tube here
is about four millimeters below the top of the stem.
You're gonna need to remember that for the step later on.
So whilst grabbing the fork there,
I'm just gonna slide the stem off the steerer tube there.
I'm just gonna let this hang down.
So I'm taking up my tube spacers
that were under the stem there.
I'm gonna put them on the side
with the top cap next to them.
Now the next thing is this top plate of the headset,
you wanna slide this up.
So that is your top cap there.
Then underneath that you have a spacer
and the compression ring there,
which is a split ring that pushes into the top
of the headset there.
So make sure that stays in there as well.
Then you have a washer and the top bearing race.
Now I'm just gonna let the fork slide out
of the head tube there.
Now sometimes you might find that the lower bearing race
sticks inside the head tube.
So if that's the case, just keep your hand under that
so it doesn't drop on the floor and get dirty.
In this particular case,
it's come out on the actual fork steerer.
So just to show you that,
that is the lower bearing race.
Then there is a little spacer there or a seal,
and then the actual crown race there
is still part of the fork.
Now this is something we're gonna need to remove,
but before we do that,
we're just gonna give everything a bit of a clean.
Whilst the fork is off the bike,
just take this opportunity just to inspect the frame,
make sure everything's sound,
there's no rough, there's no damage, or anything like that.
So just take a look at the new fork and the old fork
and see the differences.
So the first one, you're gonna notice,
is the steerer tube on this new fork is quite a lot longer
than the old fork.
So that's something we're gonna have to trim down
to the correct length.
Now also, the crown race for the headset
is still on the old fork,
so you're gonna have to remove that.
Now there's two main time of crown races.
There's the ones that push on,
and then there's those that have a split ring.
This particular one has a split ring on it,
which means this is gonna be a lot easier to take off,
and you don't need specific tools for that.
Now also note, that on mountain bike forks
you often see this little recess here just underneath.
That's really handy
for getting in an old, flat, blunt screwdriver or a punch
to loosen your crown race and get this off.
Now of course that is not the correct method for doin' it,
but it's one that I've been using for many years,
and as long as you take your time
and use an old screwdriver,
you never wanna use a good, new screwdriver
'cause you wanna keep them sharp for obviously reasons,
it's absolutely acceptable to remove it like that.
However, on certain forks,
let's just say you've got a posh fork with a carbon crown
or it's a very lightweight fork,
you don't wanna be sittin' there with a punch
and hammering the actual crown race off.
So it is a very specific tool for that job.
Now, I'm well aware that most of you won't have access
to a toolers,
but I just wanted to show you this
and show you why it's an important tool.
So this the Park Adjustable Crown Race Puller .
So this actually goes upside down in a work stand,
and you got these three blades here.
The idea is you put your fork steerer tube into this,
and then you secure these blades
underneath the actual crown race,
and then you simply turn the dial
to pull the crown race off.
You might question that this is a bit of an excessive tool
for a job like this,
but actually if you think that on road bikes, for example,
you got super lightweight
and actually very delicate components on there
like carbon fiber steerer tubes and that,
the last thing you wanna do is use a punch
and put a big gouge into that.
So these are the best way,
and they're really, really good
for removing the crown races.
But of course, fully aware that most people won't have 'em.
I just wanted to make you aware that they do exist.
So if you have problem getting one off on your own bike,
you can always just take your fork
down to the local bike shop and maybe a pack of biscuits,
and hopefully a mechanic will have one of these,
and he'll help you get your crown race off.
(bike wheel spinning)
So, I'm literally doing a like for like fork swap here
so I'm gonna measure the steerer tube
with a trusty tape measure.
Now make sure when you use a tape measure,
you take into account the bit on the end there
can actually move up to two or three millimeters.
So make sure that is flush against the fork crown.
So, in millimeters here,
so what am I, one, seven, four.
174, so that is the measurement
that I need to make my cut mark on the new fork.
So let's get that measurement there.
Measure it up on the new fork there,
and then I've just got a fine flat screwdriver here
to make a little score mark for reference.
Now this is something before you cut,
I can't emphasize enough,
measure twice, cut once.
You do not want to mess this up and cut this too short.
I've seen this happen a lot of times,
and it ends up being a very expensive thing to get around
because to replace your steerer tube on any fork,
it means replacing the crown and upper legs as well,
and that will of course mean a full fork service
to do so as well as the price of that component.
So make sure before you cut,
you've measured, you've checked it,
you've measured again, you've checked again.
The more times the better to be honest.
(bike wheel spinning)
now if you're not doing a like for like fork swap,
and you actually wanna change the front end of your bike
maybe by allowing the steerer tube to be longer
and for more spacers,
the best way to do this is to put the fork on the bike.
So put the crown race on, assemble the stem on there,
get it in a position you like,
then make a mark above the stem.
Then from that mark, you need to allow
for that three to four millimeters below that,
which is where you make your cut mark.
And the reason for that
is when you tie it in the stem preload cap on the top,
it gives enough room to actually pull out everything
together to preload that bearing correctly.
If it's a flush fit,
you're never gonna be able to tighten
or adjust the bearings so there's no play.
And of course, if you ride a loose headset,
after awhile you're gonna damage the bearings
and you could damage your frame as well.
(bike wheel spinning)
Now when it comes to actually cuttin' the fork steerer,
there's a few different options available to you.
Now the classic, or the good old fashion way,
is by using a hacksaw.
Make sure you've got a nice fresh blade on there,
and it's tensioned correctly so it can't snap
or actually go skewer.
So that is a good solid way of doing it.
Now if you use a hacksaw to do this,
you're definitely gonna need a metal file afterwards
to make sure there's no burrs,
it's nice and smooth on both the inside and outside.
As for keeping the blade straight,
there's a couple different options for you here.
Now you could get a dedicated fork steerer tube
cutting guide like this one,
and the way this works is it's clamped into a vice ideally,
and basically you put the fork steerer tube through here,
and you line up your cut mark
with the hole, very simple, by eye.
You'll then tighten this clamp up,
and that is where you make your cut mark.
That is a fairly foolproof way of doing it.
It's the official way of really cuttin' down a steerer tube
and not gettin' it wrong.
You make a cut mark here, the small piece comes off,
this is the piece you keep, job done.
However, not everyone's gonna have access to these tools
and of course this is a bike shop spec tool.
These are really good.
This is actually my own person one.
Over the years, I've cut a lot of steerer tubes,
but you might not.
You might only ever do this a couple of times.
You might not be able to justify one of these.
So something I do recommend keeping ahold of
is an old handlebar stem.
Now you can use your old handlebar stem
as a guide in a similar way.
You can slide this onto your steerer tube,
and using your multi-tool you can tighten it up
in a relevant place just like so.
And then that is where my cut mark is.
Make the cut mark there,
it makes a nice saw guide,
'cause it's an old stem,
I'm not too fussed if it gets anymore damaged,
but it's a good use of an old product.
Now the final option available to you,
and this is a really handy option
if you don't have the luxury of having a workbench
or a dedicated space to work on your bike,
is by having one of these little fellas.
This is a pipe cutter.
So simply put, your steerer tube would go in here,
you adjust the disc until it contacts it,
and you rotate it around until you cut the steerer tube
at your specified point.
It gets a very accurate cut.
They're not the cheapest item of kit,
but they're really useful.
And like I said, if you don't have the luxury
of having a space to work on your bike,
that can be better
than having to have a bunch, a vice,
a steerer tube guide, and a saw.
Okay, so really the correct way of doing this
is by using a vice, using a saw guide, and using a hacksaw.
Now you can get away with doing a mark of the hacksaw,
using some sort of guide, improvising,
by maybe leaning on it on a soft surface.
You're not gonna damage it,
but you won't beat this
for an accurate and correct way of doing it.
So just lining up that in the vice there.
Now of course this vice isn't bench-mounted here,
but it's mounted to a really heavy lump of wood,
and it's more than enough for this purpose.
So the important thing is to make sure,
if you've, for example, got some accidental other scratches
on your steerer tube,
you don't accidentally line of those up.
This is your moment of measure twice, cute once.
Can't emphasize that enough.
So that is the line.
I've even made a little arrow by it this time,
so I know it's the one I wanna cut.
So I'm just gonna slide this in,
and then, by eye, I'm gonna line this up in here,
and then I'm good to make my cut mark.
So, this is the moment of truth.
If I've got this wrong, it's not gonna fit my bike,
and I'm sure you probably wanna see that to be fair,
but I don't want that to happen.
So, make sure you hold everything nice and tight,
and nice, clean strokes on the hacksaw.
(sawing)
Get it going, keep going until you're through basically.
And this is where having a nice sharp blade
will be beneficial for you.
(sped up, high-pitched sawing)
(tube clattering onto floor)
So there we go.
That is cut off there,
but while I've still got the vice here,
just gonna slide it through a little bit more.
We're gonna tidy up as well.
Just be careful cos there could be some very sharp burrs
around the edge there.
You're gonna get your metal file,
and you just wanna make you just smooth off the edges.
(filing metal)
Now also, you just wanna use the rounded edge
of your metal file,
and do the same on the inside of the steerer tube,
because you do need that to be smooth
in order to fit your headset preloading star fangled nut.
Now one very important thing to remember,
when you cut your steerer tube down,
you're gonna get all these metal, like, metal swarf,
metal filing, metal dust everywhere.
You do not want this anywhere near the mechanical bits
of your bike, especially bearings.
So make sure you clean your fork completely
before you put it back together
and get it in the bike.
If you gonna blow this stuff on the floor,
make sure you sweep it up and get it out of there.
You don't want this stuff anywhere near the moving parts
where it can interfere with that.
(bike wheel spinning)
okay, so the folk steerer tube is now trimmed down.
So the next thing is to reinstall the crown race.
Now, as you know this earlier on,
this one has a split race
which means I have the luxury of literally sliding this on,
pushing it in place.
Doesn't need seating.
However, if yours does need seating,
then there's couple options open to you really.
Now, the budget version is to use a punch or a screwdriver
to tap it into place.
But really you don't wanna be doing this
unless you specifically know what you're doing
because you can damage the surfaces
that the bearings sits on.
It won't sit flush.
That means you'll get tight spots in the headset,
of course the bearing will wear,
it's not a good scenario.
Now the correct method is
by using a crown race setting tool.
Basically a big, hard, toughened tube.
You get different alloy inserts.
They would sit over the actual race itself
and you basically pick the one
that sits the neatest on there, slide this into position,
and then you would strike it with a mallet
to actually set it completely straight.
And of course in this case, I don't need to do it.
(bike wheel spinning)
so you're nearly ready to put your fork back in your bike,
but the last thing you need is to install one
of these little fellas.
So this is a star fangled nut,
and basically it sits inside that steerer tube
and it has thread on the inside there for an M5 bolt.
And the reason for that is,
your top cap with that bolt will screw into that,
and they basically pull everything together
so everything is aligned and taunt with the bearing
so the bearings are held, they're preloaded,
there's no movement, everything works correctly.
So this has to go to a predetermined depth.
Now there's really a couple ways of doing this.
There is the budget way of doing it,
which would be using an M5 bolt.
I wouldn't recommend using the one
that you're actually using for your bike,
use a spare one,
and you're gonna hafta hammer this into place.
Now you can do this,
but there's no guarantee
that A, you're gonna get it to the correct depth,
or B, you're gonna get it in straight.
So that is, if you're comfortable just using a mallet
and not using the correct tool, you can do it.
However, there are dedicated tools
for actually setting this to the correct depth.
There's a couple of options available.
So the older tool is like this one.
You literally screw the star fangled nut onto it,
you line it up with the fork,
and you hammer it in with a mallet.
The other option is one of these,
slightly more advanced version of that same thing.
You screw the nut on, you align it over the steerer tube,
slide that down, and hit that home,
and, again, it's the correct depth to set it inside.
Okay, so now with the star fangled nut installed
into the steerer tube and the crown race in place there,
I'm good to put the bike back together again.
Now although you don't need to have grease in there
to actually lubricate the bearings as such,
it makes a really good barrier
against water gettin' in there,
so I do recommend placing grease
onto the actual crown race itself,
and then just around the cup on the inside
of the frame here,
just where the bearing will sit.
So, the seal and the lower race now,
gonna sit them straight onto here.
Then taking care to make sure the cables
are orientated correctly,
just gonna put the steerer tube
back into the head tube there, slide it into place,
locate that bearing at the bottom there,
and then put the headset back
into the same place as it was before.
So firstly that bearing goes into place,
again, I'm just gonna put a smidge more grease
just around the top,
just to act as a waterproof barrier,
and then just make sure your steerer tube
is fairly clean there,
and you're ready to start putting in the other bits
of the headset in.
So the split compression ring slides into place there.
Have to make sure that the steerer tube
can be pulled up nice and taunt against those bearings.
And you got that seal that sit in there.
Make sure it has been given a wipe actually.
Seal sits into place nicely there.
There's the top cap of the actually headset goes on.
Then there are my stem spacers,
and then it's a case of running that all the way
back in again.
Now I've got my nice little gap at the top there.
Just need to put this stem cap back on,
and then nip this up.
I'm not gonna preload it too tight just yet,
I just wanna make sure it's all on in the right place.
Just make sure everything feels right.
Now it's time to get the brake back on.
Now something I definitely recommend doing,
putting some fresh thread lock on those bolts.
Okay, so there we go.
Successfully fitted the fork to the bike.
The very last thing you need to do
before doing a safety check,
just make sure your headset bearings are preloaded properly.
So with the stem clamp bolts,
that's the ones that hold the stem to the steerer tube,
with those loose so you can turn the bars,
line up your stem so it's inline with your front wheel.
Good way of doing this is by standing over the front wheel
and holding it between your legs,
and you get that nice line of sight,
lining up your top tube of the wheel and the stem.
And then tighten this bolt.
You don't wanna be over tightening this.
This is literally, the tool has no movement,
but the handlebars can still move freely.
As soon as there's any friction there,
you've gone too far
and you can actually damage the bearings.
So with that nice and snug now,
I'm just gonna tighten up my stem clamp bolts.
Everything is in place, we're good,
the wheel is safe, the front brake is safe.
That means we're basically good and ride the trails.
The last remaining thing would be to set the fork up,
and we're actually gonna look at that
in the next Essentials series on GMBN Tech.
So there we go, we successfully swapped a fork,
trimmed it down, and reinstalled it with a new one
onto a bike.
So hopefully that's been a useful video for you.
It's a really fun upgrade to do,
and definitely does improve the handling of your bike
if you're gonna get a better fork on there.
For a couple more great videos,
click down here for our Essentials playlist.
So, that is all the basic stuff,
but it's really essential for everyone to know that stuff.
And if you've got press fit bottom bracket issues,
click down here.
That has everything you need to know about maintaining it,
and making sure they don't creak.
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