How To Fit A Press Fit Bottom Bracket

How To Fit A Press Fit Bottom Bracket


– I know, I know. Press fit bottom brackets. Some of you out there
are huge fans of them and others may be not quite such lovers. Now I’ve actually never
had any problems with them on any of my own bikes, but I am aware that some
people that had have. But let’s a look today on
how to fit them correctly, using the correct tools, importantly, because I do understand
that some of you out there do, in fact, hack or botch
your way to fitting them. So what exactly is a press
fit bottom bracket then? Well, essentially, it’s
some bearings that house within an aluminium or plastic cup, which are then pushed inside of the bottom bracket shell into place. Now, on the flip side of this, is the traditional style bottom bracket, which is threaded, as you can see here. And so they’ve been
obviously pushed into place. It uses a spanner, which
interconnects with the notches and then threads inside of
the bottom bracket shell. Or, in fact, another option
is just a simple bearing, which is pushed into the frame by hand and then you have a
little clip which holds it inside of the frame. Now there are some exceptions to the rule. Take, for example, this one
here from Will’s Manufacturing, which is a push fit bottom bracket, but it threads together. “Why?” you may ask. Well, it’s actually to
stop any creaking of cups inside of a frame, which
some frames do sadly have a slight problem with. So if you’ve got notches on the side of a press fit bottom bracket, or any bottom bracket for that matter, it means you’re gonna need
to use a spanner to remove it rather than smashing it out, which is quite a crude term
for what we’re gonna do very shortly. So what are gonna use
them to actually remove those bearings that I’ve
quite crudely just said, “smashed out of the frame”? Well, firstly, you are
either gonna use one of these or one of these. But more information on
these two products shortly. What about fitting the new bearings then? Well, a bearing press is
definitely recommended. I cannot recommend it highly enough. They do come in a huge variety of options, and also budgets too, so
there’s no real excuse out there if you are a
particularly competent home mechanic to get
yourself one of these. (RELAXING MUSIC) So what are we gonna do then? Well, let’s get into
the nitty-gritty of it. First up, you’re gonna want
to remove the chain set, and keep a close eye out, too,
for any spacers or washers in between the cranks and
the bottom bracket itself, because if there are any in there at all, make sure you lay them
out in the correct order, so that when it comes to refitting, you’re doing it correctly. Now something to consider,
when removing these cups from the frame, is that the
manufacturer of these cups, in most cases, assumes that
they are no longer any good. So they are gonna get marked
internally with the tool when you remove it. And if you are botching your way out of it using a hammer and a screwdriver to smash that bottom bracket cup out, well, you’re gonna get problems like this. That’s another reason why not to botch it. (RELAXING MUSIC) Let’s look, then, at how we remove a press fit bottom bracket
from a standard size axle diameter frame. When I say, “standard size,” in this case, smaller than 30 millimeters. But, as many of you know out there, the standard of bike components
are changing almost daily. And who knows? Maybe a 30 millimeter will be the standard by the time this video comes out. So, how are we gonna do it? Well, we’re gonna use one of these tools. So this tool from Park is
actually designed to remove those press fit cups. How does it work then? Well, at this end, we’ve got
some sprung-loaded endings and then at this end
we’ve got a nice flat one. So, we’re gonna push, first of all, through the bottom bracket hole, the blunt end. So, in effect, it’s gonna
go through like this, and then these compressed sprung ends, if you like to call it that, are gonna slowly compress, and
then as you push it through, they actually go out into position. Then you can do the magic. Now using the bottom bracket
bearing removal tool, you’re gonna want to thread
it through the axle hole. And then you’re gonna find
a point where you hear a satisfying click. a satisfying click. (CLICKS) That’s the one. Now, with a hammer, you’re
gonna wanna give that tool a few sharp blows to remove these cups from the bottom bracket shell itself. So make sure that you’re
either prepared to catch it or, if not, where it’s gonna
land is not on something valuable or fragile, because, yeah, I know
someone who happened to and they got into a
lot of trouble at home, believe me. So, with a few sharp blows… (HAMMERING) (HAMMERING) (HAMMERING) You’re gonna start seeing the
actual bottom bracket here, just moving out of the shell, then you’re in a good state of affairs. Just keep hammering away. (HAMMERING) (HAMMERING) Now if you’ve got a sleeve inside of the bottom bracket shell, it’s worthwhile just picking
that out and removing it. That way you can give it a good clean up as well as it makes the
next part of the job just a little bit easier to
get in behind the bearings. (RELAXING MUSIC) So, before we go ahead and actually fit in the replacement bottom bracket, what we’re gonna do is just
clean that up a little bit. So spray some degreaser in
there, get yourself some cloths, and wipe away any grease,
dirt, grime, stones, and wipe away any grease,
dirt, grime, stones, anything like that, which could,
in fact, have got in there. That way, putting in
the new bottom bracket is gonna be a lot easier
and also it’s gonna go in a lot straighter. What about, then, if you’ve got a PF30, or PressFit-30 style, bottom bracket? It’s loosely the same principle
as what we’ve just done, but you use a different tool, so something like this one here from Park. And it would thread through
the bearing, like so, and then, you imagine that
this is the other side, it just sits up against
the inside housing there. And then, technical term coming up, a few sharp whacks with
your hammer and bang! It’s at that bottom bracket shell. As easy as that. Now, like I said earlier on,
you could risk botching this, but it’s really not worth it. How would you botch it? Well, you’d use a hammer and
a punch, or a screwdriver, and, essentially, you
would hit those cups out one side at a time. And because you’re not
hitting them out evenly, you risk distorting the actual
shell of the bottom bracket. Which, in the process, could
actually destroy your frame. Doesn’t sound quite so… Appealing now does it, I guess, if you could ruin that frame. No, use the correct tools. Now, when it comes to
fitting or re-fitting that press fit bottom
bracket into the shell, this is where a little bit
of extra time could make the world of difference for you. So if you’re the person
out there who claims to have had a creaky
press fit bottom bracket, then think about applying
some adhesive primer and then some retaining compound, allowing them both to dry, of course, before fitting the bottom bracket, therefore taking up some of
the tolerance and differences between the two components. And then if you’re fitting
a press fit bottom bracket into an aluminium-lined shell, then think about using some grease. It’s gonna make it going
in a little bit easier as well as reducing the possibility
of any creaks out there. Then, finally, if you’ve got
yourself a carbon-lined shell, then the general consensus
is actually to not use grease at all, because many people think it’s gonna swell the carbon, when, in fact, that carbon
shell is actually covered in epoxy, so it shouldn’t be… Having the opportunity to
even swell that carbon. So I’m a little bit on
the fence with that one. Personally, I don’t bother
applying any grease to it. And then if you’ve got titanium, then yet you could use some anti-seize or you could use, in fact, some grease. (RELAXING MUSIC) Now to install a BB86 or
PressFit-30 bottom bracket Now to install a BB86 or
PressFit-30 bottom bracket is exactly the same process. And every mechanic I know
out there actually does it the same way. So they install both cups into
the frame at the same time. Ultra important here is to
use the correct size drifts to actually press those bottom
bracket cups into the shell. Why to use those? Well, you’re gonna get
them evenly going in, so, potentially, if you don’t use that, you could well destroy the bottom bracket, and then, even worse, destroy your frame. And nobody wants to do that, do they? Nobody. You want to, now, actually start pressing the bottom bracket cups into the shell. So you should be able to
get them just gently started by hand, and make sure they’re
not going in lopsided at all. And then with your bearing
press and the drifts, begin to tighten that bearing press, begin to tighten that bearing press, so that the cups are actually
going into the shell. If there are any signs of
them not going in straight or lopsided, whatsoever, then remove them and restart the process. Because continuing to do
so could make the inside of your bottom bracket
shell slightly elliptical and, well, that’s gonna
give you that dreaded creak. Now, once you are satisfied
that they’re going in nice and straight, continue
just gently turning that bearing press until the bearing cups are flush up against the
bottom bracket shell. Once that is done, don’t go any further, because you could risk
damaging the bearings of the bottom bracket. And if you’re really muscly, unlike me, then you could even, in
fact, destroy the shell. I do know someone who continues to do it and they wrote off a frame. So there we are, you’ve managed to do it. Now it’s just a case of
refitting that chain set, and remember, of course,
if you did have any washers or spacers, make sure you put
them on in the correct place. It will make things much easier for you when you go out riding, believe me. Now do remember, as well,
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