ken thomson

SKF-608 2Z bearings.

Does anyone have experience with these bearings?

I was planning to clean and re-lube all my bearings. Popped them out of the
wheels and then started to see if I could take one shield off. I noticed
that the shield retainer seemed particularly picky - so I googled the
bearing type - SKF 608-2Z and found maintenance notes on the SKF website -
http://www.skfsport.com/cleaning.htm .

SKF say the shields are not meant to be removed and the bearings cannot be
serviced. On inspection - it looks like they have gone to a fair bit of
bother making sure you cannot remove the shields on these bearings.

Is it worth continuing to try and forceably remove a the shields so I can
clean and re-lube the bearings? Or should I just accept what SKF say and
brush them clean? Or perhaps buy new servicable bearings?

Cheers,
Ken.

mikevanerp2001

You could remove just one of the shields from each bearing and then
clean them. Since the bearings are "non-serviceable", you'll then be
left with a bunch of bearings with a shield on just one side. That
doesn't matter as you can install the bearings in your wheels with the
shield on the outside and the uncovered side of the bearing facing
into the wheel which will prevent dirt getting in.

http://www.londonskaters.com/article_bearing_maintenance.htm

http://www.londonskaters.com/article-speed-skate-bearing-cleaning.htm

Cheers,
Mike.

dsr

I would buy a set of serviceable bearings with better shielding. ABEC
1 and ABEC 3 bearings have too loose a tolerance for good shielding.

ABEC 5 bearings come in different styles, I have tried many different
kinds of bearings and the ones that work for me best are designed with
a sliding metal shield.

On the inner hub of the Boss ABEC 5, for example there is a notched
recess machined into the inner bearing hub. The metal shield is
slightly spring loaded so it slides on the "lip" of the inner hub.
The lip is wide enough to allow for bearing eccentricity. These
bearings will stay quiet and well lubricated for 30 or more skates as
long as you don't skate through puddles. Removing a side shield to
clean the bearings is a little tedious since you have to pry out a
circlip, but you only have to remove the shield once.

I have never tried the sealed bearings or any higher ABEC rated
bearing such as the 7 or 9 rateed bearings. I doubt if I would be
able to tell the difference in speed. On a 13 to 20 mile solo skate
the ABEC 5 bearings let me cruise along in the double digits just
fine.

Pack skating or skating behind friends with bicycles you can pick up
several miles per hour due to less wind resistance. In that situation
frame length makes a bigger difference than the bearings ABEC rating.

I have been tempted to try the sealed bearings but heard they were
noticeably slower. I can notice the difference in speed between ABEC
3 and ABEC 5 bearings so I might not be happy if the sealed bearings
are real slow.

Some bearings like the Swiss style bearings have a nylon cage and
others such as the sealed bearings have rubber parts so you can't use
harsh chemical solvents to clean them. You can use carb spray WD40 or
whatever you like to degrease the all steel bearings with metal cages.

I am just going to use my triflow bike chain lube with teflon to lube
my skate bearings in the future. There is not enough teflon in a drop
of triflow to clump up, it's almost clear fluid. Since I always clean
the bearing first before I lube them any teflon residue gets removed
each time I clean them. With just over a hundred miles on a set of
triflow lubed bearings, they are still quiet so It definately lasts
longer then WD40.

b fuhrmann

They really don't go to "a fair fair bit of bother making sure you cannot
remove the shields" but they don't pay for the extra parts and labor to make
them removable. Notice that they call them industrial bearings. When an
industrial machine needs maintenance it is cheaper to toss out the old
bearing and put a new one in.

I tried it on similar bearings and ended up bending the internal cage on
many while trying to get the shields off. I won't bother with it again.
Too much work (in my opinion) for salvaging cheap bearings.

If you get one shield off per bearing you can clean them and use them with
the open side to the inside of the wheel.


I'm a fan of the theory that brushing/wiping the outside will run the risk
of pushing material into the bearing and if anything remove the additional
seal formed by the layer of dirt. Besides, I'm inherently lazy and prefer
to not spend time maintaining equipment instead of playing with it.


That is a good thing to do while experimenting with what to do with your old
ones.
Do they run gritty right now?

If so, you could try the dunk them in oil method.

Put them in a container and cover them in light oil. Leave them sit for a
day or two to let it seep in.

Take them out and lay them on a paper towl so that most of the excess oil
will wick out.

The theory is that the oil lubricates the bearings and that the rolling
balls will push the crud off to the sides instead of in the path.

I don't do this but have a friend who has and said that it actually works
reasonably well and is worth the small amount of effort expended.

bob cardone

That's the trick to making your bearings last. Don't wipe them, let
the dust build a cover around the shield , and they will last forever
( providing they don't get wet)

Bob