– 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. As always, click on the round globe to subscribe to GMBN Tech. We love having you here, and make sure you tell
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