Rich Payne: Welcome to the Tech channel, everybody. It's me,
Rich Payne, and I've given Doddy the day off. You know what? He's been buried in there quite
a lot lately and, do you know what, he fancies a bit of a ride, so I've stepped in for him.
Fear not, we're going to be delving into the tech realms just as much though.
Today we're actually talking all things bottom bracket. We have two different types of bottom
bracket with us today. We have this one, threaded, which screws into the frame and the bearings are
generally housed externally. Then we have this little bad boy press fit where the bearings are
encased, if you like, in this nylon shell, and that is [sound] forced into the bottom bracket
shell of the frame. You also have things like BB90 where the bearings are pushed directly into
the frame. However, today we're talking all things press fit, and we're going to be looking at how to
remove and install one of these correctly. [sound effects]
The offender then, your creaky old, grimy bottom bracket. It's been buried in there for years
and you've just not really touched it, and it's making some horrible noises. Why is that? Well,
servicing this kind of bottom bracket by its very nature is quite tricky because it's a sealed unit,
it's pressed in there. The only way of getting at it is taking it back out. Over time,
dirt and grime and crap like that can build up in there and cause the thing to sort of move
ever so slightly and creak and groan. These noises can also occur if the bottom bracket
wasn't installed correctly in the first place. Because the tolerances are so tight, if these
things aren't put in dead straight, or the correct retaining compounds or greases aren't used, well,
then again it allows dirt and water and grime to get in so that these things will start walking.
To start with then, what are we going to need to carry out the task? I'd strongly not recommend
laying into your beloved frame with a bit of wood, a hammer, and a flat-headed screwdriver. Although
you can get away with this, not ideal. If you can lay your hands on the correct tools, that is the
definite way to go because the best tool for the job is the right tool for the job. All right. It's
going to get messy, so some latex gloves are highly recommended, along with some blue roll
actually. If you've got a bit of blue roll knocking around it's always good to have.
As for the actual tools themselves, here I've got a bottom bracket bearing removal tool. What
that is is a splined piece of metal. As you can see, you pull that through the frame,
these splines compress, [sound] pop out, and then when you hammer them back through with
this, [sound] what they do is create an equal force all around the inside of the bearing cup
so that it pushes it out equally, rather than, like I said, if you're hitting it with a
hammer and a screwdriver like tap, tap, tap, tap. These just hit nice and evenly through.
I've got an 8 mil for taking my cranks off. My cranks need a 5 mil as well because they've got
a pinch bolt on them, much like a Shimano crank. I have got here, this is the bottom bracket press.
Now, it's slightly different to a normal headset press because it does have various attachments
to it to fit perfectly inside of your bottom bracket depending on which one you're going
to use. We'll dig those out a little bit later. If you're pressing in aluminum cups, then you're
going to need this. Some alloy assembly compound that's going to stop anything reacting, sticking,
or seizing together. We've got this, which is our primer. This is for our nylon cups going
into our carbon frame. Then last but not least our retaining compound. That's basically going to help
stick it in there and stop any kind of walking or creaking, hopefully, that way. Finally,
what else have we got? Ah, this brake cleaner. Something that evaporates afterwards just for the
final cleanup should any grease and grime get anywhere, just to make things nice and tidy.
Right then. You've got the tools, or as close to them as you can possibly get your hands on.
It's time to get started on the bike, but we need the other side. [snaps fingers] Ah, perfect.
On this bike, I'm going to need to start off by taking the non-drive side off first, and for that,
I need my 8 and my 5 mil. Now, what you can do is drop the bike into the hardest gear to
the chain's slackest. On this bike I've got clutch as well, so I'm going to push that
forward. It just makes pulling the cranks out a lot easier. There's no tension on the chain.
On my Canyon Lux here is a set of rotor power meter cranks, which require an 8 and a 5 mil Allen
key to take them off. With the 5 mil I'm going to undo the pinch bolt, and then with the 8 mil
take the main bolt that holds the crank on. I'll slide the crank off, and then with the spacers
and washers that are behind it, I'll lay them out in order on the workbench so that I know exactly
how to put them back on. With that dropped all the way down into 12, if you've got a SRAM mech,
push that cage forward, lock it out. That's going to make that chain nice and slack.
Look, if you've got a Shimano mech on there, undo the mech. It's going to do the same thing. It's
going to take all the tension off of it. Now, I've got a little chain device on here, so I'm going to
just undo that. Pop it up out of the way just so that it makes getting the chain on and off
a little bit easier, and then hey presto [sound], off she pops, hanging freely. In an ideal world,
the crank would come out nice and easily and just pull straight out. [grunts] Not happening today.
This is where your mallet comes in. I've got a nylon ended, so it's got a soft ended one. Don't
be laying into it with a lump hammer, and I'm just going to persuade her [banging], and out she pops.
Almost. Hang on. Ah. Ta-da. Crank's out then, and it did take a little bit of persuasion,
but what can we see? Well, the bearings themselves actually run still pretty smooth. It is however
a little bit grimy back there. You can see from the backside of the chainring here and also this
seal for the bottom bracket that is pretty wet. Obviously, there's been water ingress and there is
grime and grit in there as well. Like I've said that can work its way in, and it has,
so we're going to clean this all up, we're going to pop this out, make sure everything's clean,
and then pop it all back together. Cup removal time then, and this is where this
specific tool really comes into its own. Like I said, it's going to slot behind that cup and push
it out nice and evenly. If you can get your hands on one of these I'd strongly recommend it. If you
are going down the hammer and screwdriver route then please just be careful. You can gouge the
inside of your frame, you can damage the bearings and the cups if you are going to be pressing them
back in, so just do be really careful. Right then. We'll slot that one in there
like that, pull it through and you'll hear it click. [click] Bingo. That means it's located
properly on the other side of the cup. Now, when you're hammering out watch out because
these things can tend to fire across the room, so just put your hand in front of it. If you want
to protect your hand you could have a rag there instead, and we're going to start laying into her.
[hammering] The cup's nearly out. A few little taps and [bang]
bingo, she's out. Pull that one through, slot it through from the other side, and repeat the
process to get the other cup out. [sound] Hear the click. [click] [hammering] Ta-da.
Diagnosis time then. The old bottom bracket, well, it came out fairly smoothly, so the
retaining compound and the primer actually did its job in there before, and allowing this to
still be removed without tearing into the frame. But as you can see this is very wet, and there's
a lot of water inside the bottom bracket shell there as well. Having a look at the shell itself,
there's no damage to the carbon, there's no scouring, there's no signs that anything was
installed incorrectly. It really is just a case of the weather doing its job over time and needing a
bit of a tune-up really. I'm going to make sure everything's clean, the shell's nice and clean
and dry before I start to press anything back in. When cleaning out the bottom bracket shell on the
frame, just use a bit of blue roll to give it a good wipe around. This should do the trick
just fine. Try not to use anything too abrasive or rough as this could actually damage the frame. The
same goes for the bottom bracket. Give it a good once-over checking everything ready for the grand
reinstall. Just to eliminate absolutely every possible chance of creaking then it's well worth,
if you've got a bit of time, taking the chainring off as well. Undo this lock ring on the back, wipe
it all off, give it a jolly good clean everywhere and assemble. That way you know that there is no
dirty parts going back together and there's no, or absolute minimal, chance of creaking.
When it comes to pressing it back in and you've checked everything over, it's clean,
tidy, shipshape, there's no damage to the frame or the cups themselves, there's a few steps that
you need to go by. Now, today we're pressing our bottom bracket into a carbon frame. Now,
whether you're pressing in a new one or the existing one back in, there are a few stages
and bits of prep that you're going to do. First up, it's an adhesive primer. You're going
to paint that either directly onto the shell of the bottom bracket or the bottom bracket itself,
and that's going to give a good key for this stuff here. This is our retaining compound,
which is actually kind of like a thread lock, if you like, to hold it nice and in place. Like
I said, this stuff goes on first. It takes about 30 minutes to dry, so I'm going to paint this on,
and in that time you could well bake a cake. The primer's in and it's very nearly set. Now,
the primer is very, very, very important because it essentially stops this, the retaining compound,
from gluing your bottom bracket, your nylon cups,
or your plastic cups to that carbon frame. If you don't use it then you risk very much damaging the
frame badly, as in pulling actual shards of carbon out because it will glue it together.
If you are going aluminum into aluminum, then this is what you're going to need;
an alloy assembly compound. That stops the metals reacting and fusing together essentially,
but always check with the manufacturer what they recommend because there's lots of different
schools of thought out there on what you should use. Some people still use the adhesive primer
even on the aluminum to aluminum so really have a little look, see what the manufacturer recommends,
and just make sure though that you use the right stuff. Whether you are aluminum-aluminum,
aluminum to carbon, nylon to carbon, make sure you use the right compound for the right stuff.
Crunch time then. It's pressing the bottom bracket in, and that is where this little beauty
really comes into its own. It's a dedicated bottom bracket press. If you don't have one of these,
which I'll be honest most people don't, you could use a headset press. It works almost just as well.
The only difference is it doesn't come with this little beauty, these adaptor cups which
sit nicely inside the bottom bracket. You can see it sits flush, there's no wiggle there, so it
presses it in evenly and straight the whole time. Like I said, bottom bracket press, well worth it.
If you're going to go down the hammer and wood route, then,
oh Lord, I would be blooming careful, because as soon as you start whacking that thing in, one,
if you don't do it nice and straight and evenly you can cause some proper catastrophic damage to
the frame, even splitting it, I've seen in the past. That is something that you don't want to
do because warranty will not help you there. If it goes in wonky, well, then eventually it's got to
find its way in straight and flush. That's going to be at the expense of what we call walking,
where the cup sort of wanders [sound] top and bottom like that to find its
place to sit properly, and then you're just going to have gaps in there where creaking will occur.
Don't forget, obviously, retaining compound. That's going to be applied directly to the
cup. We'll just dab it around here. There it comes. It's fairly thick, so it will just go on
nice and easily all around there. Sorted. Cool. I'm going to assemble that up on the press
now and we'll get them squished in. Once applied, pop the cups on their correct
side of the bottom bracket. Sometimes these aren't side-specific but just check first.
Slide it through and then attach everything, making sure everything's nice and straight so
it tightens up evenly when pressed. It should be looking fairly smooth
as it goes in, but be careful not to overtighten and potentially split the bottom bracket shell.
Bish bash bosh then. You've done it. Well done. Congratulations, everybody. That press fit bottom
bracket is exactly back where it should be, or that brand new one is in and your bike is
running creak-free, smoothly and ready to shred, but we've still got to reassemble our bike. We
need to get the cranks and everything back on. Well, once all that's back on it should hopefully
look a little bit like this. [snaps fingers] Oh. Well, there we have it. Back together
in one piece and working great, ready to hit those trails, and what a lovely bike it is.
That's it from me on the Tech channel. Thank you very much for joining me, ladies and gents. I hope
you're now clearer on removing and reinstalling press fit bottom brackets. It's been real great
fun to be on the channel today. As always, why not give it a little subscribe? Let me know
what you thought down below in those comments, and I will hopefully see you for another Tech
video soon. Cheers, everyone. [00:12:22] [END OF AUDIO]