How To Replace Frame Bearings Using A Bearing Press | MTB Maintenance


– Suspension mountain bikes rely on a well-operating rear shock, and of course, all of
those pivots to be smooth and operating well in
order for the back end to track properly and do its job. Now due to the way
mountain bikes are ridden in a variety of conditions,
from time to time, you’re going to need to
replace these bearings, or at the very least,
give them a good service. Now if you fancy having
a go at that at home, it’s not really a hard job to do, but it can involve some specialist tools. So, this is what you’re going to need, and this is how you do it. (whoosh and clank sound) Now before we get started, it’s
just important to remind you that all mountain bike
frames are different. It’s very unlikely that
the one that I’m going to show you here is going to have the same bearings as your frame. Now some bikes have the bearings as part of the rear end of the frame. Some of them, they’re included
as part of the main frame. Some of those bearings
are going to be located in the swing links or
the rockers on the bike. And, of course, they’re all going to use slightly different methods
of getting the bearings pressed in there, and also
for extracting the bearing. For example, if you’ve got a
massive lower-pivot bearing, your main pivot of the
bike, if those bearings are housed on the main
frame, it’s quite likely they’re going to be similar bearings to what you’d have in hubs,
so quite a big bearing, or even bottom brackets,
like a huge bearing. If that’s the case, you’re going to need something like a bottom bracket bearing installation device,
or the same for a hub. In my case, I’m using a Nukeproof, and on that particular bike,
the bearings are quite small, and they’re all based on
the back end of the bike. So I’m going to need quite
a compact bearing extractor, and also, putting the
bearings back in again. Now this is just a guide to demonstrate the technique to you,
and the things you need to bear in mind when doing this yourself. It’s going to vary very
slightly for each manufacturer. If you’re unsure about this, double-check on your manufacturer’s website. There should be a service
manual with your bike, or at least, available online, and it will have an exploded diagram, showing you the order
those bearings and washers go into the back end of the bike. As always, if you’re unsure
about this sort of thing, consult your mechanic at
your local bike shop first. So the tools you’re going
to need are going to vary depending on the type of bike you’ve got and the type of bearings
that are in there. Now we can only recommend that you use the correct tools, but obviously a few different methods you can have. The safest way is using a dedicated bearing press and extraction tool, so there’s various
different ones on the market to suit different types of bearing and different parts of the bike. And, of course, in a
way, they’re expensive so there are other options
for this sort of thing that I’m sure all of you
are going to look at. Now you could use a
simple punch and a mallet, that’s definitely going to do the job of getting the bearing out of the bike, but it’s going to be very easy to damage that bearing, and if you do so, you’re obviously not going
to be able to use that. But, more importantly, you don’t want to be damaging the frame
when you’re taking it out. So if you use that technique, you’re pretty much on your own. Be careful; it’s possible, of course, but just take your time if
you’re going to do that. And again, for putting
the bearings back in, you could use a block
of wood and a mallet. I’ve done that in the past successfully on some designs, but obviously, you’ve got to use your common sense. You can’t just do this
on any part of the bike, you can only do it on certain parts of the frame that are safe to do that. Again, can’t recommend you do that. I always recommend using the
correct tool for the job. But if you insist on
doing a homemade method, you could make something similar to this fairly easily at home. So get yourself some threaded bar, some quality nuts, and then get yourself a selection of different washers that match up the size of
your bearings on the bike. That’s going to be the safest way without having the correct tool of getting your bearings
back into the bike again. So I’ll show you how to make one of those in another video, but for this video, I want to show you the
correct way of doing it, the safest way, and the best way. So for this particular job I’m doing on my Nukeproof Mega
290, it doesn’t actually need a bearing change, but
obviously if we kept waiting for things to wear
themselves out on bikes, you’d be waiting a long
time for these videos. So I’m going to be taking out
my perfectly good bearings and reinstalling some more
perfectly good bearings just for your benefit. In order to do that, I’ve obviously got the bearing kit dedicated for my bike, I’ve got a compact
bearing installation tool, I’ve got threadlock, a
little grease, rubber mallet. Got my little tin with my ferrules and cable end caps and nipples in there. I’ve also got a chain master link, because I need to take my chain off and my rear mech off the bike, in order to make sure my chain has its least likelihood to snap, we want to put it back together, so
we put a fresh link on there. And, of course, the crucial Allen keys. In my case, a four, five, and a six. (music) Okay, so first things
first, is the preparation before you get started
taking those bearings out. Now obviously your bike
in the works down here, if you haven’t got works down, put your bike upside down on the floor, take the wheels off, then you need to start taking the components out. So, in this case, my
bike’s in a workstand, wheels are off, need to
take the rear brake off, need to take the chain off, need to take the rear mech off, the shock off, and, in this case, I need to take the cranks off because
I’ve got a chain guide that’s obscuring the
lower pivot bolt here. Now if you’re lucky enough to have a bike that’s got internal cable routing and look really nice, then this process is actually a bit harder for you. As you see on my bike here, the rear brake caliper’s
got external routing, so I can simply snip the cable ties here and the calliper can dangle neatly so I don’t have to
rebleed that afterwards. If you’ve got internal
routing, when you do that, you’re going to have
to rebleed your brake, because you’re going to have
to take the calliper off to get the hose out of the swing arm, in order to take the
swing arm off the bike. If that’s the case, and you’ve got Shimino or Sram brakes,
there’s bleeding videos in the description
below, so you can follow that process once you’ve done this. Same applies for the
rear mech of the bike, or the rear derailleur,
you’re going to need to cut your inner cable here in order
to take the rear mech off. In my case, I’ve got an external hose that runs all the way to the shifter, and I’ve got two cable ties here. So I can cut those, and
take the rear mech off, and let that dangle. I do, however, need to split my chain, which means I’m going to have to use a fresh link in it when I do that. And, of course, I need to take my cranks off and the shock off. (music) Now what we’re left with is
the back end of the bike. Now this still feels
really, really smooth. You can get your bike to this stage even just by taking the rear shock out and cycling your rear
suspension up and down. You’re going to be able to identify if your bearings are
knackered pretty easily. Again, there’s no noise here. As you can see, it’s
really free in movement, so that suggests they’re
in good condition, but we’re going to go ahead and pull all of these pivots out now,
get the back end off, and start showing you how to remove those bearings and inspect them. (music) The back end is off, I’ve
got everything laid out on the workbench here, now
I still need to separate the chainstays from the seat stays, but before I do that, just
before I go any further, I’m just going to give
this a quick wipedown, and then we’re going to
start inspecting things and seeing what sort of
condition the bearings are in. So, personally, I don’t
like to get two hands on with this sort of stuff. I’m just going to give
it a bit of a wipeover with a rag and some solvent on there. I’m going to try and avoid going too near the bearings or that sort of stuff. I’m not looking to completely clean this, just get the worst off. It’s a good time as well,
whenever you’re doing this sort of thing, just
to inspect your bike, to see if there’s any paint missing, or unusual markings, or even cracks, you know, if you haven’t
done this for some time. They do happen, bikes aren’t invincible, and it could just be a hairline crack but, nonetheless, it could still grow. I’ve carefully taken the whole back end of the Nukeproof apart
now, so I’m left with the chainstay, the seat
stay, and the swing link, as well as all of the gubbins. Now this is the point when you can decide if you’re actually going
to replace your bearings, or if you’re going to do a
bit of a guess at fixing them. Now bear in mind, by
replacing the bearings, they’re obviously going to last longer, but if your bearings are
just a bit dry for example, and they’re still working okay, you can do the ghetto hack
that I showed you recently, where you pick off, very delicately, the rubber seals on both sides, force out all of the sort
of gunk that’s in there with a degreaser, and then grease them and put the caps back on,
that was in my headset video. Now it’s a really good thing to do on a suspension bike, because those sort of things do sort of
need regular attention, especially in the sort
of conditions I ride in. But, bear in mind, it’s
never going to last as long as changing the bearings outright. And something else to factor in is if you’re changing a bearing or two, you may as well do the whole
lot so they wear evenly. If you’ve got some bearings that are absolutely knackered, of
course, recycle those, get rid of them, but the
bearings that you think are still with some life in them, I’d recommend doing
that ghetto fix on them, and keeping them as spares, ’cause they will come
in handy at some point. So just work your way around, you can feel the bearings manually, they’re almost smooth actually, that’s not too bad, no reason
for actually changing that. Again, I’m going to emphasise this by taking it out just to show you this. But you can work your way around and you can make those decisions yourself on the bearings on the bike that you’re actually going to change. Some of the bearings get a
lot more use than others. Some are smaller, some
are bigger, some are more susceptible to sort of
lateral play and twisting. Other ones seem to never
get any wear at all. Here’s the main ones, the main pivot, and actually that one’s
a little bit rough, but just dry, I suspect,
it’s nothing major. We’ve had a lot of wet weather here, so there’s a good chance that all our stuff has just been washed out. So, next step is to start
removing these bearings using the bearing extraction tool. Again, this is something
you can do yourself with a punch and a mallet,
or an improvised tool, but there’s a high chance
you’re going to damage the bearings and the
frame when you do this. So if you do that, take
care, and of course if you do do that, you are on your own. So just take that into account. So now the back end
completely off the bike, I’ve decided I’m going to
remove all the bearings and start fresh, put some
new bearings back in. So that means we’re going to need to get the bearings out of the bike, and it means working in some small,
confined spaces like this. So to do that, I’ve
chosen to use this little compact setup, so it’s
not quite the offering that you’d get (mumbles) in full-size mechanical ones for workshops. This is more like for the
advanced home mechanic. I think they’re still
quite reasonably priced. They’re priced for a kit
with two length of bar. So in this case, I could use the bar in this quite narrow
space here quite easily. And then you choose the
male and female adapters for extraction and pressing back in again according to the bearings on your bike. Now on the website, you
choose these by just looking at the number that’s on the seal of your bearings, and that correlates to the particular male and
female parts that you need. So, in this case, for these bearings, I’m going to demonstrate
on the main pivot bearings that are down by the bottom bracket here. So for this particular
tool, the red bits are for extracting the bearings,
and the blue bits are for installing the bearings afterwards. So for this particular bearing, you’d put the extraction tool, slide that into place, slide
the shorter piece in there, just nip that up, and put the larger piece that sits up against the frame. Now carefully just tighten
this against each other. As you can see, this piece is pushing the bearing out and
into the larger section. There we go, and that is
the first bearing out. And there we go, first bearing
removed from the frame. Now of course you need
to inspect the frame, make sure it’s not damaged in any way, give it a bit of a clean, wipe it out, make sure there’s no sort of stress, damage, cracks, or anything like that. And if you’re intending
on reusing these bearings for spares later, you
can do that ghetto fix, which I showed you in the headset video. The link to that is in
the description below. And in that video, I
demonstrate how to remove the rubber seal from both
sides of the bearing, flush the bearing out, and put
fresh grease back in there. And it will continue
working quite happily. But in this case, I’m
removing all of these bearings and we’re going to put some
fresh ones straight back in. Now next up we can look at
the swing link of the bike, so that just has a single
bearing on each side. I’ve taken one of these out a second ago, and I’m just going to
demonstrate another one to you. This is where this compact
tool comes in handy, because it’s a very awkward
little space to work in, that you would probably struggle
with a lot of other tools. As you can see by looking
on the inside here, you can see the lip where
the bearing sits in place, and this is one of those
lipped bearings, like so, which means it can’t be
pushed out to the inside, it has to be pushed from the inside, out. So important to take that into account before you damage anything. So removal side of the
tool, pushes into place, slide in the small side of the tool, which just about fits in there neatly. I think you’ll find this fits most suspension bikes quite well. And then, this one was the number 11, slide that on there, the larger piece of the tool onto here,
nice part of the tool on the backside there,
and then give it a good couple of turns, I can see it just moving, any second now, and it’s
just going to pop out. There we go, and there’s the bearing successfully out of the
swing link of the bike. So there we go, there is my back end of the bike, minus all the bearings. Time for the new bearings to go back in. Of course, first things first, give it all a good clean, make sure those bearing surfaces are clean, and then, one by one,
you’re going to start pushing the bearings back
in using the right parts of the tool, and just taking
a bit of care to do so. So that is all of the bearings out of the back end of the bike, frame has been cleaned, it’s ready now to have all of these nice, new, shiny bearings pushed into the frame. Of course, I just want
to do it one by one, taking my time, and putting a little bit of grease on each one, so let’s go. First I’m going to do the swing link here. Just a small amount of
grease on the inside here, just to make sure it slides in properly. Now this is the side the
bearing is to be pushed in from. This is the part of the bearing tool that slides it back in place. You have a backing plate
that pushes up against there. Just slide this into here. When you’re pushing
your bearings into frame is to check at all
times that everything is aligned properly, ’cause you do not want to damage your frame by you trying to push a bearing in that’s not straight and is never going to
be sent home correctly. Now this one is really going in nice and neatly, and we’re home. Remove the tool, and
that is the first bearing successfully pushed back into
the frame, and it feels great. So I’m going to repeat that process with all the other bearings on the bike, just taking my time to make
sure everything is back in. Again, think of the old proverb
“Measure twice, cut once”. It’s important with this sort of thing, you do not want to rush
it, so there we go. That is all of the bearings into the back of the frame, ready to reassemble. Now something that’s absolutely crucial when you’re reassembling, of course, is making sure the correct
bolts and pins and washers go in place just as when
you stripped the bike down, but make sure to use some threadlock when you’re reassembling them. Okay, so just a bit of threadlock
on each one of the bolts. Carefully slide those back into place on the back end of the
bike, making sure that any washers that were previously in there also go back in, and
make sure they’re just lined up, and in it goes. When the rear triangle
is fully reassembled, and I bolt it on to the back of the bike, I’m going to go around
with a torque wrench and just double-check all of these to manufacturer’s settings. With something like
this, I highly recommend doing that, because you don’t want them to come loose, you don’t
want to overtighten them either, because
that can damage things. So we’ve got the back end of the bike is on, I’m just going to
work my way around now and make sure the last
few bolts are in place, put the shock back in
there, and then of course brace and gears back on there. Now if you’re unlucky enough to have internal cable routing on your
bike, you’re probably going to need to bleed your rear brake when you put it back together. So if you want to find out how to do that, click down here for how
to bleed a Sram brake. There’s a Shimano brake link in the description below as well. And, if you need to do your
gears on the way back in, click up here if you want
to find out everything to do with tuning your rear derailleur, putting a fresh cable in there. As always, please click
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