Harder wheels - Faster bearings

I really hope Ron decides to answer Jeremy Paxman's, oops, I mean Joolz's detailed questions specifically because this is a fascinating debate.

What does Ron do with the Lip fungus when he's in his NASA style clean roon it must be a contamination risk.

Jools i fkn love ya!!!!!!!

What does Ron do with the Lip fungus when he's in his NASA style clean roon it must be a contamination risk.

Skate Bearing lab located at rear!






Hope's Rockin' Ron has sense of humour!

YMCA fucking rips for skating man! Have you not seen the YMCA parks in the US?

Google YMCA Skatepark for an eye opener. Including this beauty:





If you have to grow a 'tache to get in, I'm ok with that!

YMCA fucking rips for skating man!

For real dude? Like, FAR OUT. I'm stoked, bro!

super super stoked? Hallelujah!

The main word I brought back with me from AZ was 'awesome' everything is 'awesome'

Pronounced without the 'w' so in an english accent it sould a bit like 'ass-hum'

That Encinitas YMCA park is one of the parks I would most LOVE to skate Paul. I just couldn't resist the 'tache jibe.

That Encinitas YMCA park is one of the parks I would most LOVE to skate Paul. I just couldn't resist the 'tache jibe.

Get thee to Middlesborough then, bar pool coping the bowl at Prissick is supposed to be an exact replica of the Encinitas pool. Big mother allright.

http://i21.ebayimg.com/05/i/000/77/b1/fe4f_1.JPG

They may have great Skateparks at the YMCA but i still wouldnt want to drop my soap in the shower.

But dropping the soap aside, You can get yourself clean, you can have a good meal, You can do whoever you feel ...

So not quite rocket science, but aparently there is some science
http://www.exploratorium.edu/skateboarding/index.html
But not much, and not as Geek McTweek as us ( some of us )

I haven't been skating long, but I know a little bit about bearings now

Thats my sector 9 cruiser, purchased in april this year. Ridden most days for 20min or so. Came with Sector9 Greaseball abec 5 metal shielded bearings which I never cleaned. About a month ago a rear wheel started to squeal and would not spin freely. So I put in some cheap mini-logos. I went noticeably faster on the flat which shows the degradation that occurred with my Greaseball(s).

below is my little popsicle. Its a cheap shop package, bought coz I didn't have a clue about modern skateboards in may this year. By cheap I mean decent cheap local skate shop package - shop brand deck, bullet 52mm wheels.... and not Argos quality (we have Target over here)

Now confined to just once a week in the street, but done considerably more milage than the sector9 with many hours in the parks. It came with Abec 1, 608zz brand. Caked with dirt sticking to the grease on the metal shields, never cleaned, spin as freely as the day I bought them.

But isn't that just the luck of the draw? - not all of my Greaseballs gave up on me - just one wheel I think, I didn't bother to check, just replaced the lot.

Also a big problem I see with the arguments here is that no-one seems to be currently running top of the line Bones Ceramic bearings. But then who would be so stupid as to splash out $101 on ceramics.....

.... But then who would be so stupid as to splash out $101 on ceramics.....

ok somebody had to do it

this is my new Chocolate stick 4 weeks old. It started life with Krux 4.0, cored Spitfire Tracers 54mm and the cheapest bearings I could get - mini-logos.

but being a skate geek earlier this week I installed Bones Swiss Ceramics

so now identical setup, 1 week of almost daily ramp testing, before I stuffed my knee yesterday So I could make some objective comparisons!

well i have tested bearings in engines over and over looking for tiny improovements in horsepower.From my own experience i know that the fit of the inner race to the truck axle is so poor that this fact on its own throws the this one is better than that one argument into dissaray.You can put the best ceramic bearings in anything but if there is any give in the mounting of anypart where the bearing fits then ossolation occurs and all the force ends up going through a tiny part of the cage rather than the whole of it and you loose so much efficency.Because of this it doesnt happen in a non regular way,meanibg it is hard to repeat any scientific test,If you really find the need to make the ride smoother then firstly id have some axles machined to the bearing was a very tight fit on the axle,this on its own would vatly improove the bearing efficency...The reason it does not bother me is cos im not pulling 7ft backside airs!!!Thats my 2 penneth....thankyou.xxx.

hey teapot thats useful to know that youve done that. I've got a couple of comments, in a car the significant bearings are the mains on the crankshaft and the big-ends or whatever they called where the rods connect with the crank. The motorcycle bearings are the same principle as this?

this is significant coz mains and big-ends are quite different to skate wheel bearings. No cages, no ball races, just smooth machined shells clamped around smooth machined bare crank. The gap measured in thousands of an inch is still enough for the crank to move marginally, but oil is forced by the oil pump into a hole in shell (or is it the crank? i forget) and the crank when spinning sits on a ridge of film of oil when spinning with an oil ridge in the "lower" of the crank - coz pressure is downwards from the pistons. So the tiny play is necessary to get this ridge - hot rod enthusiasts have extra play - and in this situation the performance tweaks are gained not so much from buying expensive bearings but machining the crank to achieve the exact gap they are after. But the reason why this gap works is because there are lots (well 4 or something) mains arranged in a series with a decent length of crank in between each bearing which stops the crank from twisting one way or another.

So comparing just 2 bearings arranged in series on a skateboard axle which are placed close together on an axle that is effectively too small and being clamped by flexible urethane rather than cast steel crank case then this means that there is going to be sideways twist. So this would explain the different choice of bearing principle needed ie ball races capable of dealing with this twist - and the spherical nature of the balls are capable of taking load from different angles, so this overcomes the slop problem to a certain extent so maybe some bearings do it better than others? eg. different size/number of balls set some specialty skate bearings from others.

Not just that but the hot rod enthusiast can get custom machining of the crank, but the skate nerd can't adjust gap between ball and cage and gets whatever comes out of the box. So maybe some skate bearings get the more optimium gap between ball and groove in cage to get the grease film just right? so maybe some skate bearings are better than another?

anyway if what you are saying is true then the practical out of the box way to achieve low oscillation would be perfectly fitting spacers with the wheel nuts done up tight to prevent axle twisting inside the bearing series?

my 2 cents to throw on top of your 2 pennies!

er yes I'm not pulling 7' airs, or anything at all for that matter - hurt my knee

cheers,

Mike

I have a scientific bearing rating system. I keep all my bearings that aren't currently on one of my boards on a piece of string in the filth at the bottom of my skate bag. These are mostly skanky old nmb's and other random cheap bearings accumulated over 17 years. I scientifically test them by individually turning them in my hand to see whether they:-

a. turn
b. feel like they are full of grit
c. make funny noises
d. fall apart

Anything that falls apart gets thrown away - gotta have my standards. Anything else gets a liberal spraying with WD40 or any other random lubricant-style liquid that I have specifically been told not to use on bearings. I select the eight "best" and stick them in my wheels, and go skating and don't do 7ft airs, but they feel pretty fast to me.

so far this has been a blind test as all my bearings look the same, but since my wheel loss incident I now have 6 bones red bearings to go "in the bag" as it were, so i'll report back my findings - do some graphs and stuff, see how it pans out.

mr j,you are talking about 4 stroke motors,i am talking about 2 stroke motors which do use ball bearing and needle rollers in the mains etc...and my knee hurts!!!!

i have just had a nice chat to Mr Bearing dude...from an Exeter bearing co..
you see the problem with ball races is their inability to deal with side loads..
Apparently
what i need according to mr bearing is some ... "at this point he lost me in techno babble"
not ball races ..
if what he say is correct then our bearings spend about 30 to 40% of their lives working propperly turn a corner = side load...

i change ALL the bearings in my engines every race for ultimate horseepower and for reliability..my feelings are new is good (unless you deal in antiques)..so if you think your bearings are best past new..buy some more..im board of this bearing talk,its too much like work!!!my name is teapot,i have my coat,i know lots about bearings,and ive left the topic,goodbye..

So comparing just 2 bearings arranged in series on a skateboard axle which are placed close together on an axle that is effectively too small and being clamped by flexible urethane rather than cast steel crank case then this means that there is going to be sideways twist. So this would explain the different choice of bearing principle needed ie ball races capable of dealing with this twist - and the spherical nature of the balls are capable of taking load from different angles, so this overcomes the slop problem to a certain extent so maybe some bearings do it better than others? eg. different size/number of balls set some specialty skate bearings from others.

like i said above and got shouted at by a drunken tramp.. THATS WHAT DUAL DURO WHEELS ARE FOR!! (and i know mullen uses those metal core freestyle wheels)..

they use a harder core to stop bearing twisting and misalignment of the races which will of course impede the overall super spinnyness of the wickle shiny balls (yes thats the technical term)

Indeed:

You gets what you pays for, basically. Cortechs + Rockin Ron's = A pretty penny but also = FAASSSSTTT!!!!

I don't know if he'll do it for Cortechs yet, but Ron will supply custom fit spacers for each wheel. Not just a particular make of wheel, but each individual wheel, then ship the whole package to you assembled. Or at least labelled with which spacer goes in which wheel. This sort of thing must be akin to the custom machining of bearing shells/cranks for top performance in the automotive field.

I see Rockin Ron remains noticeably silent after Joolz's direct questions...

Cos' his tash has grown over his keyboard

fuck you

i've developed an amazing hormone juice that will make my balls go 400% faster...

for heath and safety reasons i've tried it on my face first....



regards

ron

I see Rockin Ron remains noticeably silent after Joolz's direct questions...

Probably because he hasn't check back here, I'm sure he would if he knew about the question.

....
so far this has been a blind test as all my bearings look the same, but since my wheel loss incident ..... I now have 6 bones red bearings to go "in the bag" as it were, so i'll report back my findings - do some graphs and stuff, see how it pans out.

I remember reading about your wheel loss incident.
my first reaction was mirth. My second reaction was to get my skate key and check all the wheels on all my boards.

cheers,

Mike

ah - 125cc class 2 stroke? with such little engines I would imagine squeezing every watt of power is crucial.

mr j,you are talking about 4 stroke motors,i am talking about 2 stroke motors which do use ball bearing and needle rollers in the mains etc...and my knee hurts!!!!

I didn't know that, then what you were saying is highly relevant to skate bearings - reducing up and down oscillation plus what I call diagonal play.

Let me guess the reason for ball races/rollers in 2 stroke motor cycle mains are :

crank length much shorter - diagonal play greater
2 stroke - shake and vibrate more putting uneven forces in all sorts of directions?

cheers,

Mike

PS lets hope our knees get sorted soon

...they use a harder core to stop bearing twisting and misalignment of the races which will of course impede the overall super spinnyness of the wickle shiny balls (yes thats the technical term)

yes!
and just how much twist can we get in urethane? when i needed to change my bearings I went to skateboard.about.com howto section and it instructed me to use the end of the axle to wiggle and twist out the bearing. Didn't need much force either. No way could I do that in a metal engine crankcase. Of course I had the advantage of leverage on just one bearing, but imagine hammering up a flat bank and not hitting it absolutely square on

cheers,

Mike

Indeed:

I don't know if he'll do it for Cortechs yet, but Ron will supply custom fit spacers for each wheel. Not just a particular make of wheel, but each individual wheel...

yep i'm with you there trevenen, not just cores to reduce twist but correctly fitting spacers to help with that too plus distribute axial forces across both bearings. Axial force - sideways load on bearings. With no spacers all the axial load gets placed on bearing next to the hanger (or the wheelnut if in the other direction).

With spacers =>load more evenly taken up by both bearings.
=> less pressure on any individual ball/ring
=> grease film less likely to break down
=> less friction

edit---> plus as I mentioned earlier the spacers allow the wheel nuts to be done up tight and thus reduce the up and down movement (oscillation) and wobble that happens on the under-sized skateboard axles.

cheers,

Mike

i have just had a nice chat to Mr Bearing dude...from an Exeter bearing co..
you see the problem with ball races is their inability to deal with side loads..
Apparently
what i need according to mr bearing is some ... "at this point he lost me in techno babble"
not ball races ..
if what he say is correct then our bearings spend about 30 to 40% of their lives working propperly turn a corner = side load...

i think those loads can be understood in simple skate-nerd terms. What he is saying doesn't sound entirely true to me. eg. the front 4 main bearings in a 4 stroke v8 crank aren't designed for sideways load at all. just a sleeve on machine crank if I remember rightly (i've only souped up an engine once- holden monaro 256 cu inch V8 - never again!). So the crank will readily slide axially(sideways) except the rear main bearing has a flange to take up that sideways load.

but skate ball races handle load differently - your balls don't fall out every time you turn a corner!

taking a look at the diagrams on http://www.dynaroll.com/catalog/pag010.htm we can see that they sit in a groove on the inner ring and the outer ring. The spherical nature of a ball can take load from different directions and the groove prevents sideways slip. Nevertheless how well do they handle sideways load is a good question - there are such measurements as axial play...

the inner ring is smaller in circumference to the outer ring, so the balls will not roll entirely without friction - less distance to roll on inner ring means some slip is going to occur. Plus the nature of a ball in a groove will not roll without some slip on the surfaces. So I would think that getting the grease film right is important.

hmm on the other hand looser groove => less ball to groove contact => less fritction. But looser groove => more osccillation => bad? I'm confused now.

cheers,

Mike

fuck you

i've developed an amazing hormone juice that will make my balls go 400% faster...

for heath and safety reasons i've tried it on my face first....



regards

ron

Lots of good questions going on......I'm taking myself out of this debate as I would only be talking out of my arse from a scentific stand point. From riding on the ceramics, I still feel like they are the fastest bearing I have ridden on to this point but I don't have anything to back it up other then just riding on them.

Sam...I'm still trying to understand why would photoshoped your ginger hair out of this picture...It's okay to be ginger friend.

anyway I'm off for a skate, anyone else?

anyway I'm off for a skate, anyone else?

Depends on what bearings you run Smiler

anyway I'm off for a skate, anyone else?

Depends on what bearings you run Smiler

but do you have cored wheels and machined spacers?

cheers,

Mike

So Ron

..Now on the 'Sceintific tests'......

Are you really saying that when placed in a skateboard and tested in a lab where your bearings are the only variable, your bearings make the board run 40% faster?t...

yes, just how are skateboard bearings lab tested? simulating hitting flat banks, carving, kickturning, pumping. Linear tests would only give a small piece of the speed experience.

cheers,

Mike

...Lots of good questions going on......I'm taking myself out of this debate as I would only be talking out of my arse from a scentific stand point. From riding on the ceramics, I still feel like they are the fastest bearing I have ridden on to this point but I don't have anything to back it up other then just riding on them.
....

i'm talking out of my arse, I don't have any scientific knowledge of bearings, i'm just looking at pictures of them on web sites and trying to imagine the forces that are on them when skating. I used to hang out on a surfboard building forum and there are some serious fin nerds studying NACA airfoils and all sorts of equations, some fin companies have been dragging fins in water tanks and behind speedboats to measure drag, but at the end of the day they can't simulate the forces involved in carving and slashing so the only real test is to go and ride them. So I'm with you on that one OMA.

I wanted to get some Rockin Rons with machined spacers and bones wheels,. but the website say they are sold out of that wheel deal. So I went into my local skateshop and the only ceramics they had were the Bones Swiss (these come with spacers). The shop owner was overjoyed when I asked for them, not so much for the money I think, but coz he could talk to me at great length about bearings. One of the things he said was that some wheel manufacturers mould their wheels with marginally too small a gap for the stock spacers to fit with the bearing face flush against the urethane. However as luck would have it the stock Bones spacers fitted perfectly into my Spitfire Tracers I could rotate the inner ring with finger on one side and watch the other rotate from spacer contact with my Swiss bearings pushed right into the cavity. On the axle with nut done up tight, but not so tight as to squash spacer the wheels would spin, not as freely as loose mini-logos no/spacers, but still spin.

anyway I can see that these things are more of an emotional rather than a speed thing, coz no one seems interested in knowing if the Swiss ceramics made my board go faster in the min-ramps!

so in that case I think I'll just carry on arguing with myself....

cheers,

Mike

So Ron

..Now on the 'Sceintific tests'......

Are you really saying that when placed in a skateboard and tested in a lab where your bearings are the only variable, your bearings make the board run 40% faster?t...

yes, just how are skateboard bearings lab tested? simulating hitting flat banks, carving, kickturning, pumping. Linear tests would only give a small piece of the speed experience.

cheers,

Mike

nevertheless though, there are a number of non skating tests that can be given to bearings on the test bench. And wouldn't it be reasonable to expect that if a bearing failed some of the basic tests then its not going to be a top performer in the skatepark?

So to take this basic ABEC tests, which are concerned mainly with radial runout and face runout plus accuracy of the bearings external dimensions.

Radial runout is concerned with a vertically loaded bearing, and applies to a skateboard tavelling in a straight line no sideways forces. Whereas face runout is concerned with sideways or axially loaded situation - ie. skateboard under side pressure from a turn or something.

So in practical terms radial dimensional accuracy + radial runout tests measure how much a skateboard moves up and down when pushed along the floor ie. off centre grooves, uneven ball size could cause marginal up and down oscillation which according to our resident race motorcycle boffin is bad.

Face runout in practical skateboard terms would measure much the wheels would move in and out towards and away from the hanger when pushed along the floor- sideways oscillation.

So doing badly in ABEC tests would mean that the board is oscillating up and down, and the wheels are oscillating side to side, this must be bad for speed?
and as the bearing manufactures point out, the ABEC runout tests are measuring unwanted movement after exactly one rotation and don't
measure play so there are other basic tests for play that can be done too

cheers,

Mike

i have just had a nice chat to Mr Bearing dude...from an Exeter bearing co..
you see the problem with ball races is their inability to deal with side loads..
Apparently
what i need according to mr bearing is some ... "at this point he lost me in techno babble"
not ball races ..
if what he say is correct then our bearings spend about 30 to 40% of their lives working propperly turn a corner = side load...

i think those loads can be understood in simple skate-nerd terms. What he is saying doesn't sound entirely true to me. eg. the front 4 main bearings in a 4 stroke v8 crank aren't designed for sideways load at all. just a sleeve on machine crank if I remember rightly (i've only souped up an engine once- holden monaro 256 cu inch V8 - never again!). So the crank will readily slide axially(sideways) except the rear main bearing has a flange to take up that sideways load.

but skate ball races handle load differently - your balls don't fall out every time you turn a corner!

taking a look at the diagrams on http://www.dynaroll.com/catalog/pag010.htm we can see that they sit in a groove on the inner ring and the outer ring. The spherical nature of a ball can take load from different directions and the groove prevents sideways slip. Nevertheless how well do they handle sideways load is a good question - there are such measurements as axial play...

the inner ring is smaller in circumference to the outer ring, so the balls will not roll entirely without friction - less distance to roll on inner ring means some slip is going to occur. Plus the nature of a ball in a groove will not roll without some slip on the surfaces. So I would think that getting the grease film right is important.

hmm on the other hand looser groove => less ball to groove contact => less fritction. But looser groove => more osccillation => bad? I'm confused now.

cheers,

Mike

yeah but your engine bearings arnt stuffed into the floor with gravity plus riders weight plus force at a 45 degree angle that is gonna dent the race most ardent set after a while

Just in case this thread isn't long enough here's 5000 previous posts on the subject. http://www.ncdsa.com/4/Skateboard-Bearing-Reviews.htm

Just in case this thread isn't long enough here's 5000 previous posts on the subject. http://www.ncdsa.com/4/Skateboard-Bearing-Reviews.htm

So save us the bother of reading the 5000 posts.....what's the best bearing in their opinion?

So save us the bother of reading the 5000 posts.....what's the best bearing in their opinion?

Apparently Jon is working on some super kryptonite coated Magneto bearings. But i think the consensus is Biltin bearings. They're just like the 608AB bearings from a Turbo II but slightly less rattle.

yeah but your engine bearings arnt stuffed into the floor with gravity plus riders weight plus force at a 45 degree angle that is gonna dent the race most ardent set after a while

hey, you've just managed to say in one sentence what took me thousands of words and 6hrs of online research

cheers,

Mike

....
ok somebody had to do it

this is my new Chocolate stick 4 weeks old. It started life with Krux 4.0, cored Spitfire Tracers 54mm and the cheapest bearings I could get - mini-logos.

but being a skate geek earlier this week I installed Bones Swiss Ceramics

......

well I'm shocked, absolutely no one wants to know if my $101 ceramics go faster than my $10 mini-logos

...
well I'm shocked, absolutely no one wants to know if my $101 ceramics go faster than my $10 mini-logos

ok, after a slow start, emotions are starting to heat up on rejji's wot trucks thread , so I suspect that some of you do want to know the results of my ramp testing, but dare not ask.

so for those that are interested, the answer is:

I think so


cheers,

mike

...
well I'm shocked, absolutely no one wants to know if my $101 ceramics go faster than my $10 mini-logos

ok, after a slow start, emotions are starting to heat up on rejji's wot trucks thread , so I suspect that some of you do want to know the results of my ramp testing, but dare not ask.

so for those that are interested, the answer is:

I think so


cheers,

mike

ooooooooh, I'm gagging to post on here again.

I've got a wheel/bearing test program going on at the weekend (In my non-clean room shed) and I am also going to do a Finite Element Analysis of a wheel assembly so you lot can see the interplay of the various stiffnesses involved.

Plus a few hand calcs thrown into the mix.

This thread IS going to run and run I tell ya

ooooooooh, I'm gagging to post on here again.

I've got a wheel/bearing test program going on at the weekend (In my non-clean room shed) and I am also going to do a Finite Element Analysis of a wheel assembly so you lot can see the interplay of the various stiffnesses involved.

Plus a few hand calcs thrown into the mix.

This thread IS going to run and run I tell ya

not until the weekend Joolz? Monday seems like a long way away now we have to wait

Live webcam in the shed? Pay-per-view-per-geek?

i have just had a nice chat to Mr Bearing dude...from an Exeter bearing co..
you see the problem with ball races is their inability to deal with side loads..
Apparently
..
...........
yeah but your engine bearings arnt stuffed into the floor with gravity plus riders weight plus force at a 45 degree angle that is gonna dent the race most ardent set after a while

cheers,

Mike

Mike

i believe you need one of these to test your bearings..............

[img][img]http://i110.photobucket.com/albums/n87/teapot27/COMPASS1.jpg[/img][/img]

i've looked into it - i've got a GCSE in physics so I think I know what i'm talking about*

Mr J - here is a modified version with some of the bits you missed off your diagram:-



*as long as it isn't to do with physics

If you get any side thrust on these bearings the result will be contact on one side, as per the first picture.... irrespective of the 'perfect fit no play thing'

For more bearing geekery maths check out 'Herzian contact stresses'

Herzian contact stress is pretty well the only time when maximum stress occurs INSIDE the component (usually maximum stress is at the outer surfaces)

This is why ball bearings fail by peeling/flaking..... In an engineering application anyway.... Not in a low tech agricultural application like a skateboard where they fail because of the shit and grime thrown into em.

To resist axial thrust it is usual to use two opposing taper roller bearings.
These are designed to take radial AND axial loads.

Not sure if they are available in the '608' inner and outer diameters though AND they are much more expensive ...... Wayne?

Might suit the slalom tweekers though?

thats what mr bearing man said and my brain broke

right ive got it,im off to go fishing with those blokes off discovery that catch crabs in the bearin sea,surley thats where the perfect balls are hidden!!!!

These are the bear rings i'm saving up for:-

Phew..better then bare rings

goatse..