Wheel Bearing Removal

Ok, how the fudge do I get the little beggers out?

Same goes for the suspension bearings, although they should be a little
easier.

I don't care if I destroy them completely in the process, there are new ones
going in.

I've removed the circlips (I'm not _quite_ that stupid), have suitably WD40d
everything, and have tried unsucessfully to bash the thing out by jamming a
screwdriver into the gap and having at it with a hammer. All that ends up
happening is that the srewdriver slips.

The service manual says to use special tool ABC123, but I really don't want
to pay $Arm.Leg for one.

Ok, so what's the easy way?

 

I got suspension bearings out using a bar as a drift on the reverse side of
them to drive em out

have a good look and you might be able to so the same

getting them in isn't too hard and if you want to make it easier you can put
bearings in the freezer and they will shrink and pop in easy

 

Not sure of the setup but is there any way you can apply a little bit of
heat to the wheel hub? (gas torch or the like)
Don't go overboard, just enough to warm the surrounding metal up and then
try knocking them out with the drift (read screwdriver).

Eddie

 

Enter one big drift!

Hammo

 

Which raises silly question #2:

What do you do about the layer of frost which forms on the bearing the
moment you take it out of the freezer.

I tried drowning the bearings in grease before freezing them, theory being
that'll keep the condensation off the rollers, and all that does is cause
the frost to form on the grease, so you can't wipe it off...

 

how long do you leave em in there for ??

does it matter ??

what are you going to do when it rains ??

 

Well, a fair few hours... steel doesn't have that high a thermal expansion
coefficient.

The last time I did it, it was a set of CBR600 steering head bearings.
Greased them up, stuck them back into the little baggie they came in, put
them in the freezer ~overnight, and they still needed a fair few whacks with
a soft-blow plastic mallet to get into place.

Hopefully, be able to rely on whatever seals may be in place to keep the
water out.

 

The master of the L300 carby --> Intact Kneeslider did write..

IK, Bring them around to work, we have shit loads of liquid nitrogen.


Johno

 

Thanks for the offer, but the semiconductor crew down the corridor from me
are a lot closer, and their tanks of liquid helium (4.2K as opposed to
nitrogen's 77K) would do a better job, too.

If I was really keen, I could always probably talk them into letting me dunk
the bearing into what's called a dilution refrigerator, which uses an outer
vacuum jacket, an inner Helium-4 (garden-variety helium) jacket and a
special heat exchanger pumping on a small container of He-4/He-3 (ultra-rare
helium isotope with one neutron in the nucleus, not two; they have to make
it by trapping the hard radiation coming out of nuclear reactors) mixture;
that gets down to 300mK as a matter of routine, and if you try really hard,
40mK.

Contrast that with the temperatures in our machine (which is, recall, a
camping stove compared to some of the monliths out there), which heats argon
nuclei to ~400,000K.

 

Just don't tap 'em too hard when you're putting them in...

Doug Cox.
Work to ride, Ride to work...

 

I knew that~

Johno
PS Smack said it was still harsh week - get fucked!

 

Well, _that_ makes the job easy then, we stick the bearings in the
dilution refrigerator to shrink them down a bit, then stick the wheel
into "your machine" to boil all the alloy then turn it into a plasma,
then use that magic hot metal plasma coating technique to re form the
wheels around the new bearings

big

 

Gotta admit, it'd make for an aswesome CGI sequence...

 

Yeah, except its got no fighter planes in it ;-)

big (so how mych smaller do the bearings get at <1 deg K???)

 

Intact Kneeslider wrote:

Hey Marko
What's the update on your carby problem
was it the vacuum hoses?

 

Doesn't look like it. I went through them one by one on Monday afternoon,
detached, looked over and refitted them, all patient-like. No cracks evident
on any of them. Started the faken thing up again, the noise was still there.
The more I listen to it, the more it seems like it's coming from the end of
the air duct, where the air turns through 90 degrees to go down the carbie's
throats.

They_are_supposed to make a bit of noise as they draw the air in, and what
I'm hearing is flat enough (no high-pitch component to it) for it to be
reaching me through some sort of solid barrier, but it does seem a bit
overly loud.

 

Maybe you never noticed the noise before and now that you do it has
obsessed you.

 

Pretty faken likely... my favourite game on a long-distance drive is "Was
that noise there 50km ago?", and when I do an oil change on one of the
bikes, it usually goes like this:

-drain old oil.
-refit and tighten sump plug.
-crack the top on the fresh oil container.
-check tension on sump plug.
-fill oil.
-pass the time it takes for the oil to drain down into the sump by checking
the tension on the sump plug.
-top up oil.
-check tension on the sump plug.
-top up oil again.
-check tension on sump plug.
-screw in oil filler cap.
-check tension on sump plug.
-etc.

 

do you wash your hands every 10 minutes

 

Usually a biggist screwdiver to push any spacer-tubes that might be
in-betwen the bearings, out of the way (some force is usually essential)
Then the same screwdriver or big drift to knock them out (hit opposing sides
alternately, not too hard but with sooomme oomph)
New bearing-races into freezer for about 30-60 mins, wipe frost off, coat
with **thin** layer of bearing grease.
If still tight, use hair-dryer on HIGH or heat-gun on low settings to slowly
warm the material around the seat of the race.
Make sure race goes in square, then carefully tap into place, using a piece
of hardwood or such.
If seat is recessed deeply, use old race (same orientation so you can knock
it out again afterwards) as drift-ring.
I tend to run the anglegrinder through the old race, firstly it's marked as
"stuffed" and secondly comes out easy if used as drift-ring (remove burs
first if used for that purpose).

Came across some real mongrels in the past and used a Dremel with small
grinding-cones to work my way through the hardening, then slowly and
CAREFULLY through the material, until it was thin enough to crack it with
drift and hammer. Takes forever, though...

cheers
pete