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View Full Version : Do bearing spacers affect the speed/performance of bearings?


Hot Orange
August 22nd, 2006, 11:22 AM
Hey all,

I changed the bearings on my xmax from the twincams that came with them to bones swiss labyrinth bearings after feeling that the twincams have started to perform a little worse (some of them at least).

The spacers used along with the twincams are shaped kinda like pulleys, while the ones I had with the bones swiss are simply cylindrical. When I changed the bearings I also changed the spacers from the pulley-shaped ones to the cylindrical ones, and when I tested the skates I found them to be a bit slower than before when they were equipped with the twincams.

It sounds unlikely, but I was just wonderng if the spacers had any effect in this? The pulley-shaped ones seem to stay in place better between the bearings which made me wonder. Or is it just that the twincams are better and faster than the bones swiss?

chuckboucher
August 22nd, 2006, 12:31 PM
The "pulley" shaped spacers are actually what's known as self-centering spacers. They're designed to be just what you said, easier to insert axles though.

As for the effects on performance, both should be similar, since the "saucer" part of the self-centering spacers doesn't hit anything once an axle is inserted through them and they are secured to the frame.

What would effect performance would be if you didn't put any spacers between the bearings. If you tightened too much, the wheels wouldn't roll as well.

Hot Orange
August 23rd, 2006, 11:01 AM
Thanks! Then I guess it's just the twincam bearings being faster than the bones swiss bearings in my case.

Jim White
August 23rd, 2006, 02:23 PM
Perhaps off topic, but if a person uses spacers which are too small, such that the bearings are too close together, the effect is the same as no spacer. With no spacer, or a much too small one, the wheels turn very much slower, although how much may depend on the type of wheel and frame, and certainly on how much the axle is tightened. I suppose theoretically if the spacer were just a little too small for a certain wheel that it would slow it a little.

The way to test for all this is to check how the wheels spin when the axles aren't very tight. If tightening them completely makes the wheels spin any slower, then something is wrong, such as too small spacers, or the wheels binding on the frame.

speedysktr
August 23rd, 2006, 03:12 PM
to add to Jim's point, when the wheels slide easily into the frame with no friction at the bearing point of contact, it's usually a good sign the spacers are on the small side. If the wheels roll any differently in the frame than they do freespinning in your hand, it's usually a sign of a spacer issue.:cool:

RandD
October 25th, 2009, 06:04 PM
Not sure if I missed something here, so if you buy new bearings and there come with spacers you use the new spacers, and not the old ones that the skates have (If they have them to begin with) am I right or wrong ???

gordonsanders
October 25th, 2009, 09:36 PM
It really doesn't matter which you use. Bearing spacers typically don't wear out. One of my skate geeky friends used to use a micrometer to measure his bearing spacers to be sure that they were all the correct length ( I amnotnsure what the correct length is )

online inline
October 25th, 2009, 10:36 PM
yes, the simple aanswer is that there okay as long as the spacers are sized for the bearing (the spaacer for a 608 standard bearing is different than the spacer for a mini 688 bearing), you should be fine. But in actuality, some wheel hubs are ever so minutely different so as to require an infinitesamly different sized bearing. The Intzcore alum. hub 688 wheels required a specailly sized spacer if memory serves me. But aside from a few unusual wheels like that, spacers are standard for the size bearing you use, and as long as they spin freely and don't rattle excessively, they are probably just fine.

Has anyojne found that their spacers get dinged up to the point that they affect performance? I have some with some rough shoulders, and wonder if that makes any difference. I get lazy about buying new ones, and used some old dinged up ones, or the old ones get mized up with the new ones and i lose track. But I have always wondered about that.

Sorry for spelling, frozen fingers from just getting back from running in cold and rain.

Jim White
October 26th, 2009, 01:38 PM
My position, fwiw, is that wheel, bearing, frame, and spacer are a system. The purpose of the spacer is to position the bearings laterally (along the axis of rotation of the wheel) so there's not interference with proper operation and interoperation of other parts of the system, and to avoid significant lateral pressure between bearing parts (608 bearings are only designed to bear load perpindicular to the rotational axis, not parallel to it).

Therefore, the only spacers which will work correctly are those which are of the proper size corresponding to the size of the wheels, bearings, and frames. And, no, those are not always of a supposed standard size.

Many people like simple answers. They should ignore this post.

ursle
October 26th, 2009, 01:54 PM
Not a lot of real estate to work with on my matrix trucks but normally after inserting the spacer between the bearings I would use the thin washers 7mm or 8mm depending on axle size, called speed washers to take up any slack and as they state, add speed, bearings that wobble around are only adding friction jmho,ymmv

Jim White
October 26th, 2009, 02:02 PM
Good point, I should have said that washers are an optional part of the system.

Ursle, where can those be purchased? (The only ones I've ever found are ones I salvaged from a 50-year old device I junked.)

Bill in Houston
October 26th, 2009, 02:19 PM
Not sure if I missed something here, so if you buy new bearings and there come with spacers you use the new spacers, and not the old ones that the skates have (If they have them to begin with) am I right or wrong ???

Quads or inlines?

ursle
October 26th, 2009, 02:30 PM
Ursle, where can those be purchased? (The only ones I've ever found are ones I salvaged from a 50-year old device I junked.)
8mm from bonesbearings.com look in replacement parts
7 and 8mm from connies,
http://www.create-a-skate.com/gequskpa.html
but careful, they have a terrible drop down menue ordering system, better to call them and speak to a human

ursle
October 26th, 2009, 02:36 PM
Not sure if I missed something here, so if you buy new bearings and there come with spacers you use the new spacers, and not the old ones that the skates have (If they have them to begin with) am I right or wrong ???
Spacers come 8,9 and 10mm wide and 7 or 8mm in diameter, if the old ones were 8mm and the new ones are 10mm use the old ones

RandD
October 27th, 2009, 12:53 AM
Quads or inlines?


Inlines, well if the 608 spacers are generic, what ever ones come with the bearing should all work then right???

Spacers come 8,9 and 10mm wide and 7 or 8mm in diameter, if the old ones were 8mm and the new ones are 10mm use the old ones

But if you buy a set of 608 8mm you shouldn't be getting 10mm should you???

Bill in Houston
October 27th, 2009, 02:15 AM
Inlines, well if the 608 spacers are generic, what ever ones come with the bearing should all work then right???Ya, in this case, what O/I said applies to you. Standard spacers ought to work on every 608 bearing wheel, but might not in certain odd cases.

Ursle is talking about quads, as far as I can tell.

RandD
October 27th, 2009, 02:33 AM
Ya, in this case, what O/I said applies to you. Standard spacers ought to work on every 608 bearing wheel, but might not in certain odd cases.

Ursle is talking about quads, as far as I can tell.


At the moment I have ABEC 5 and they didn't come with spacers, but the (And there in K2's) Bones ceramics do, but the ceramics are not for the K2's I am getting new skates.

Bill in Houston
October 27th, 2009, 03:09 AM
At the moment I have ABEC 5 and they didn't come with spacers, but the (And there in K2's) Bones ceramics do, but the ceramics are not for the K2's I am getting new skates.Okay, I should have mentioned this. It seems to me that bearings don't usually come with spacers. They expect your to reuse your existing spacers. If you ceramic bearings DO come with spacers, I would be concerned that they might not be interchangeable with regular spacers. It would be weird if they were not interchangeable, but it's weird that they came with their own spacers, so i don't know which weirdness wins out. You might try measuring them compared to the spacers you already have to see if you discern a difference.

online inline
October 27th, 2009, 11:16 AM
the last set of Bones bearings (Bones Super Six Swiss) i bought also came with their own bearings. They were right in the boxes with the bearings, and were the sleeve type, not the self-centering type. Since Bones Swiss and Bones Ceramics are premium grade bearings, including the spacers (usually about a $1 each) may just be a nice added bonus that ensures you will have a spacer that is not incompatible with your new high priced bearings. Another words, it is not a non-standard size, but they are just ensuring that you don't use someone elses non-standard bearing with their top-shelf product.

If you are really concerned, i would contact the manufacturer of the bearings and ask them. It's great that you're that interested.

In the past, i used to get all kinds of really useful info like spacer compatability issues from my online retailer Charlie, at Swatskates (North Texas Skate Supply). I think he got tired of doling out the info and doesn't answer the phone anymore, and doesn't really even sell skate stuff anymore for that matter. But if you are smart enough to deal with the really knowledgable online (or local) skate retailers, you could find out a lot of useful info from them, too. That's the perk of using skate retailers who are part of the sport and consequently know what the stuff they are selling and you are using.

Hope this helps. The quick answer is - get info from manufacturer, from supplier/retailer if available, and also just try them out and see if they spin freely. Like i said, given enough time, my spacers all get mixed together as the bearings become training bearings, so i end up using them with other spacers anyway, and ultimately, they are thereby checked for how they spin as a test of last resort regardless.

From what i've seen, 608 bearing spacers tend to be fairly standard - i haven't personally run across any spacers that did not work with most any bearing. But with the 688 mini-bearings it is a very different story, and spacers tend to be different sizes quite often.

Good luck.

Armadillo
October 28th, 2009, 01:45 AM
My position, fwiw, is that wheel, bearing, frame, and spacer are a system. The purpose of the spacer is to position the bearings laterally (along the axis of rotation of the wheel) so there's not interference with proper operation and inter-operation of other parts of the system, and to avoid significant lateral pressure between bearing parts (608 bearings are only designed to bear load perpendicular to the rotational axis, not parallel to it).

Therefore, the only spacers which will work correctly are those which are of the proper size corresponding to the size of the wheels, bearings, and frames. And, no, those are not always of a supposed standard size.

Many people like simple answers. They should ignore this post.

Jim,
You couldn't me more right on the mark with this statement. The whole assembly must be treated as a complete system!
What most people fail to grasp is that within this "SYSTEM" there are TWO DIFFERENT SPACING issues that affect the bearing. The wheel's hub has shoulders molded or machined into the plastic or metal. Thiese two shoulders establish a spacing inside the wheel that functions as a spacer for the OUTER RACES of the opposing bearings. The small metal spacer that fits on the axle between the bearings functions as a spacer for the INNER RACES.

Now to have a perfect bearing spacing setup, when the screws/nuts are fully tight, the axle spacer will have been squashed tightly between the two INNER races, leaving a resulting spread between them that should also locate the OUTER races so they are just barely touching the spacing shoulders inside the wheel hub. With such a result. there is nothing pushing the inner and outer races out of alignment to each other, and there is no gap between both the outer races and the hub's shoulders to allow the wheel to slide back and forth between the outer races.

So, the key goal is to have the width of the axle spacers be an exact match with the hub's internal shoulder spacing. In reality, things aren't so perfect and you really just hope to get your axle spacer to be a few .001"s WIDER than the width between the internal shoulders of the hub. You also hope that the face ends of the spacers and the hub shoulders are perfectly flat and parallel to each other, so that they don't cause the races to become relatively skewed. There is very little internal clearance in precision bearings to allow the races to be even slightly skewed relative to one another. So if the end of your spacers get dinged up, yes this can cause races to skew and pinch the balls inside giving excess DRAG & WEAR. If the axle spacer is too short relative the the hub shoulder spacing, similar result -- races get axially displaced in opposite directions and balls get pinched, thus more drag/wear results.

-Armadillo

inlina
October 28th, 2009, 03:26 AM
For the OP.....you may just need to break in the new bearings or re-fit them.

For reference, a standard inline skate wheel has a 10mm bearing shoulder width in the middle of the hub so any 608 bearing with a standard inline wheel should work with any standard 10mm spacer, self centering or otherwise.

Problems can come about when the hub is molded badly or something generates a mis-alignment from either the hub, bearing spacer or the installation of the system. The former should not be your issue as you have not swapped wheels. First thing to check is that your bearing outer race is pressed right up against the bearing shoulder in the wheel. You can go back to your old spacers if that does not fix it.

(608 bearings are only designed to bear load perpindicular to the rotational axis, not parallel to it).


That is an absolutely false statement. 608 bearings (any any deep groove ball bearing) can take a significant axial load relative to it's load ratings (static and dynamic) and the applied radial load along with the applied axial load.

A single pair of 608 bearings (ie. one wheel) with 1000N (a little over 100kg) applied at 45 degrees (354N radially and 354N axially per bearing) has an equivalent dynamic load of 620N where a 608 can take 3450N and a equivelant static load of 389N where a 608 can take 1370N.

CG

Armadillo
October 28th, 2009, 03:40 AM
For the OP.....you may just need to break in the new bearings or re-fit them.

For reference, a standard inline skate wheel has a 10mm bearing shoulder width in the middle of the hub so any 608 bearing with a standard inline wheel should work with any standard 10mm spacer, self centering or otherwise.

Problems can come about when the hub is molded badly or something generates a mis-alignment from either the hub, bearing spacer or the installation of the system. The former should not be your issue as you have not swapped wheels. First thing to check is that your bearing outer race is pressed right up against the bearing shoulder in the wheel. You can go back to your old spacers if that does not fix it.



That is an absolutely false statement. 608 bearings (any any deep groove ball bearing) can take a significant axial load relative to it's load ratings (static and dynamic) and the applied radial load along with the applied axial load.

A single pair of 608 bearings (ie. one wheel) with 1000N (a little over 100kg) applied at 45 degrees (354N radially and 354N axially per bearing) has an equivalent dynamic load of 620N where a 608 can take 3450N and a equivelant static load of 389N where a 608 can take 1370N.

CG

I forgot to say that piece of Jim's analysis was quite off the mark.
Thanks, inlina, for clarifying the the facts about deep groove skate bearings.

-Armadillo

Dave Henniker
November 30th, 2009, 06:18 PM
I've experienced binding on some wheels when the screws were fully tight, using both self-centering aluminium spacers and cylindrical steel types. Sometimes removing the wheel and pressing hard on each bearing with a bearing remover tool fixed it.

A guaranteed fix was to slacken the Allen screws off maybe quarter of a turn. This could increase the risk of a wheel become loose. I've bought some Bondlock thread lock/seal as the original stuff gets worn off.

I've had this with various well known brands. I've tried the thin washers I found in my collection, to no avail. It's funny how some wheels spin so freely when the Allen screws are really tight, and others start to bind a bit.

http://www.henniker.org.uk/images/SK8/skate_my_Powerslide.jpg

Armadillo
December 1st, 2009, 10:32 PM
I've experienced binding on some wheels when the screws were fully tight, using both self-centering aluminium spacers and cylindrical steel types. Sometimes removing the wheel and pressing hard on each bearing with a bearing remover tool fixed it.

A guaranteed fix was to slacken the Allen screws off maybe quarter of a turn. This could increase the risk of a wheel become loose. I've bought some Bondlock thread lock/seal as the original stuff gets worn off.

I've had this with various well known brands. I've tried the thin washers I found in my collection, to no avail. It's funny how some wheels spin so freely when the Allen screws are really tight, and others start to bind a bit.


http://www.henniker.org.uk/images/SK8/skate_my_Powerslide.jpg


Too-short spacer lengths or imperfections of the wheel hubs are the two most likely reasons for this. Either they are dimensionally mismatched as far as the space between the shoulders inside the wheel hub relative to the axial length of spacer, or the two shoulder faces may not be parallel, causing bearings to have outer race tilt out of alignment with inner race (which pinches the balls).

-Armadillo