Bicycle Mechanics - Are all ball bearings the same quality?

I rode on dura ace all last year for the first time. I cleaned and repacked the hubs once. I normally replace the bearings in my hubs the in the spring. My question is, do I need special bearings, or can I use the ones you get from any of the big mail order catalogs.

In other words, are all bearings created equal when it comes to bicyle tolerances??????????????

All bearings are not created equal. I believe you want grade 25 ball bearings. I don't know where you order them from but one source would be Bike Tools Etc. (http://www.biketoolsetc.com/index.cgi?id=977023412504&nr=31&b=&c=&sc=&tc=&q=ball%20bearings&s=)

I was just wondering about that the other day.. Glad you asked it captsven..
What does the grade mean? I went to the web site say Grade 200 and Grade 25..

The lower the number, the higher the quality. I'm not sure exactly how it works but I know that Grade 25 balls are harder than Grade 200.

i looked in the phone bookand found a bearing company in our town Called them and they had grade 25 steel balls i bought 250 balls to overhaul a number of pedals and hubs (different sizes of course) the charged me 3 cents each and got them instantly
catfish

I beleive theres a big diff. between steel balls (not so good) & ball bearings (the best) !!

OK, there are several things to look for in ball bearings. First is the amount of polish. The finer the surface, the greater the cost...
Secondly, there is the plating or anodizing. Better materials cost more.
Steel balls are not ball bearings. Ball Bearings have a soft metal interior, with a harder metal covering. Steel balls are steel throughout. Not good for shock bearing surfaces-you'll kill the races very quickly.

Bearing info:
http://www.howstuffworks.com/question513.htm
http://www.spirolox.com/iti/ballgradechart.htm
http://www.ntnamerica.com/Knowledge/Intro_Ball_Bearings/Ball_Brg_Materials.htm
http://www.nhbb.com/engineering/astro/materials.cfm
http://www.minebea.co.jp/english/product/bearing/smallbearing_f.html

I went to the Bike Tools Etc. link. From what I can tell, I would use the Grade 25 bearings in my Dura Ace hub.

What would the stainless steel bearings do. Would they harm the races, or would they be a superior choice?

Below is an close up (60X) image of a ball bearing. Even this bearing is smoother and more precise than the cone or cup surface. The bearings, even "low" quality, tend to be the most precise part of the system.

It is generally recommended to use the Grade 25 bearings when available.

http://www.parktool.com/images/repair_help/bearing03.jpg

ok you wizerds of knowledge got me. i called ball bearings steel balls
CF

Originally posted by catfish
ok you wizerds of knowledge got me. i called ball bearings steel balls
CF

Let's get really technical. The ball bearing is an assembly made of the races and the bearing balls. We all call the balls "ball bearings," but we're wrong.

Question: Does anyone know if the copper shot used in underpowered guns are called BBs as an abbreviation for "Ball Bearings"?

Oh, yeah...


Originally posted by captsven

What would the stainless steel bearings do. Would they harm the races, or would they be a superior choice?


Originally posted by D*Alex

Steel balls are not ball bearings. Ball Bearings have a soft metal interior, with a harder metal covering. Steel balls are steel throughout. Not good for shock bearing surfaces-you'll kill the races very quickly.

D*Alex is psychic! He answers questions before they are asked.

:beer:

For cycling purposes there are 3 or 4 grades of bearings. Grade 25 is the highest grade, 300 the lowest, with maybe grade 100 and 200 in between. Even grade 25 cost only pennies each so there is no reason to use anything else. GENERALLY, headsets take 5/32" bearings and bottom brackets and hubs 1/4", but you have to check yours because there are exceptions.

I guess there are stainless ball bearings or bearing balls, but bearings are supposed to be completely packed in greased and cleaned and re-packed regularly. If you run your bearings dry and dirty they are going to damage the cups and cones whether they rust or not. I feel the same way about stainless steel chains. If a part is supposed to be cleaned and lubed regularly rust should not be an issue so why pay 2-3 times as much for a stainless steel chain? Just the totally irrelevant opinion of an old codger.

The standards referred to in the links above seem to refer to the roundness and roughness of the bearing balls.

The cup and cone bearings used on standard bicycles are a low standard of bearing in any case. I don't believe using high standard bearing balls is any point for those bearings.

The bearing balls need to be a number of grades softer than the bearing shells, otherwise you will wear out the shells, which are harder and more expensive to replace than the balls.

I think the highest grades of bearings are designed for precision bearings, such as the bearings on stepper motors of hard drives ?

I think the most important thing for bicycles is the type of seal that the bearing has.

Originally posted by john999


The bearing balls need to be a number of grades softer than the bearing shells, otherwise you will wear out the shells, which are harder and more expensive to replace than the balls.


Yup, John999 is correct with this point. This is a basic principle of engineering. If the bearings are harder than the cups, they will cut the bearing cups. Bearings are cheaper and easier to replace than cups.

As a note from experience, I bought a bunch of bearings from a bicycle shop in China a couple of years back. I was just so delighted to see such an abundant supply of various sizes of bicycle bearings that I could not resist buying several packages for my parts collection.

I used them to repack the hubs of a front wheel. After about a month or so of riding - CRACK.. KaTHUNK; The front axle dropped down onto the bottom of the hub. The problem: the bearings had cracked and disintegrated. They were literally pulverized and crushed into shards as if they were made of clay. Unbelievable.

Needless to say, no more cheap Chinese bearings go on my bikes anymore.

Originally posted by RegularGuy

Question: Does anyone know if the copper shot used in underpowered guns are called BBs as an abbreviation for "Ball Bearings"?

I always wondered this too, that was my assumption

I looked at Merriam-Webster Dictionary (http://www.m-w.com) and the first defination for BB is

Main Entry: BB
Pronunciation: 'bE-(")bE
Function: noun
Date: 1874
1 : a shot pellet 0.18 inch in diameter for use in a shotgun cartridge
2 : a shot pellet 0.175 inch in diameter for use in an air gun

number 2 is

Main Entry: BB
Function: abbreviation
bachelor of business, ball bearing, base on balls, blue book, B'nai B'rith

So, it's actually short for B'nai B'rith? :D

Funny that old Merriam forgot "Bottom Bracket"

and bell bottoms, big bird, bouncing breasts... the list goes on!