Bicycle Mechanics - Ball Bearings

I need some ball bearings for a rebuild of a 1964 Carlton and my LBS only has grade 300 loose balls so I was looking online and found both stainless and Magnetite finish grade 25 balls. Can anyone tell me the difference between the two finishes and which are preferable?

Thanks

Don't know what Magnetite is, but I think stainless is slightly softer than "normal" BB's.

I get mine at-
http://www.loosescrews.com/index.cgi?c=Bearings&sc=Loose%20Balls&tc=Grade%2025&id=10827251054

I usually get a few bags when buying other stuff to amortize the S&H.

The 300's will be more than adequate for our use. Stainless doesn't hold up well.

Ball bearing "Grade" is a measure of roundness and the lower the number the better, so Grade 25 bearings are rounder than Grade 300. Actually for the low demands of bicycles, Grade 300 or 200 are adequate but most mechanics use Grade 25 because the cost difference is minor and that is the best readily available grade. Stainless (usually 440C) bearings are good but not guite as durable as "Chrome Steel" bearings which are also less expensive. The Loose Screws link Bill Kapaun gave is a good source as is Bike Tools Etc. (www.biketoolsetc.com) and Amazon sells bearing balls also.

That's very helpful. Thanks very much.

I use nothing but grade 25 chromium. It's probably overkill, but they're not expensive.

I just dig around in the dirt for approximately correctly sized pebbles and use them. :)

I can only imagine what that would be like to ride. I'd probably feel like indexed wheels. Sort of like the indexed steering you can have when the headset is out of whack.

As pointed out by HillRider, Grade 25 is the best for bicycle applications.

I buy mine from this people, http://www.vxb.com/ b/cos of their excellent quality and prices.

I get grade 25 for my bikes. Like Jed19, I order them from vxb.com.

Check with a local bearing house and buy in bulk.
http://yellowpages.aol.com/business/wa/mukilteo/motion-industries-inc/0-206798247/?query=Bearings+%28Whol%29&fromSearch=%26query%3DBearings+%28Whol%29%26area%3DMill+Creek%2C+WA&area=Mill+Creek%2C+WA

Check with a local bearing house and buy in bulk.
http://yellowpages.aol.com/business/wa/mukilteo/motion-industries-inc/0-206798247/?query=Bearings+%28Whol%29&fromSearch=%26query%3DBearings+%28Whol%29%26area%3DMill+Creek%2C+WA&area=Mill+Creek%2C+WA
Buying in bulk is obviously cheaper per bearing but unless you own a bike shop 1000 bearing balls are going to last a looooong time. I buy in bags of 100 for 3/16 (front hubs) and 1/4" (rear hubs) and 5/32" (Campy hubs) Grade 25 balls. They are less than $5/bag and last several years worth of overhauls on my personal bikes.

You can also buy grade 5 ceramic balls.

You can also buy grade 5 ceramic balls.
Sure you can but at what cost and to what benefit?

Buying in bulk is obviously cheaper per bearing but unless you own a bike shop 1000 bearing balls are going to last a looooong time. I buy in bags of 100 for 3/16 (front hubs) and 1/4" (rear hubs) and 5/32" (Campy hubs) Grade 25 balls. They are less than $5/bag and last several years worth of overhauls on my personal bikes.

Yes, that is my bulk too, 100 or so per package depending on size and around $5 after the governor gets his cut. Always seem to be in stock too.

I need some ball bearings for a rebuild .....

My friend at SKF asks that I correct this every time I see it.

Ball bearings are the complete assembly, including the inner and outer races, the seals and the balls. The balls themselves aren't bearings, they're just balls. If you wish, you can call them bearing balls, so they're not confused with golf balls.

Sure you can but at what cost and to what benefit?

Probably no decernable benifit, but at only a dollar a ball, I'd say that would be one of the cheaper 'upgrades' if thats all it takes to put a smile on your face. A genuine bargin compared to all the CF seatposts and stems and bars that are becoming increasingly common on commutor and weekend bikes.

Deleted/edited my mis-information....

.001mm is Campy bearing tolerance which is close to grade 25....

Sure you can but at what cost and to what benefit?

Over the years I've found that cone/race degredation is primarily from rusting assemblies NOT from over tighteneing. Ceramic balls isolate the cone from the race and thus decreases the chances of damage due to rust.

You know what's funny is that everyone says Grade 25 is bicycle grade or Grade 25 is Campy grade. 100% pure B.S. Back in the day, at least through the late 80's early 90's Campy used grade 100 bearings. Grade 100.....

I gather you have an authoritive source for this info, because you certainly couldn't tell by measurement.


Over the years I've found that cone/race degredation is primarily from rusting assemblies NOT from over tighteneing. Ceramic balls isolate the cone from the race and thus decreases the chances of damage due to rust.

+1 that rust is the main enemy of bicycle ball bearings, but I don't agree that ceramic balls would make a difference. Rolling balls polish rust off the line of contact (steel or ceramic both) seen as the dull gray line on cones and races. It's the same that the wheels of a train keep tracks rust free.

The key to rust prevention is the type of grease used. Quality greases, combined with regular use to keep them circulated are the best way to prevent rust on races, and far less expensive than ceramic balls.

As for wear, a decently cared for set of hub bearings (greased every 5-10,000 miles or in Spring if riding on salted roads during winter) will last well over 50,000 miles. For most of us that's more than the life of the bike.

Over the years I've found that cone/race degredation is primarily from rusting assemblies NOT from over tighteneing. Ceramic balls isolate the cone from the race and thus decreases the chances of damage due to rust.

Yikes! Sounds like more of a 'lack of grease' issue than a 'choice of ball material' issue!

I gather you have an authoritive source for this info, because you certainly couldn't tell by measurement.

Campagnolo's very own literature!!!!!

You know what's funny is that everyone says Grade 25 is bicycle grade or Grade 25 is Campy grade. 100% pure B.S. Back in the day, at least through the late 80's early 90's Campy used grade 100 bearings. Grade 100.....
That's very interesting and I'd also like to see the source of this information. A Campyphile poster on another froum used to insist Campy used Grade 10 (or was it Grade 5 or maybe even Grade 3...) bearing balls and "hand matched" each and every set and they had to be used as a complete set. I was always suspicious of this claim and would like to know the truth.

That's very interesting and I'd also like to see the source of this information. A Campyphile poster on another froum used to insist Campy used Grade 10 (or was it Grade 5 or maybe even Grade 3...) bearing balls and "hand matched" each and every set and they had to be used as a complete set. I was always suspicious of this claim and would like to know the truth.

It would be somewhat interesting to know, and certainly to debunk the hand matched nonsense, but does it really matter. As long as I was in the bike industry people always asked about what stuff was, rather than what it did. When I made cone wrenches and freewheel removers, I got all sorts of inquiries about the material they were made from. My answer was always that it didn't matter why or how a product did it's job and lasted, as long as it did both well.

I use the phrase " the proof of the pudding is in the eating" on the Chain-L site, and I used it years ago when selling tools, because I believe that that's the only issue a user needs to concern himself with. If I go to a restaurant where the food is consistently excellent, I don't query the chef about his recipes.

Back to Campy, given the extremely long service life of their bearings I don't need to know what grade balls they use, I already know that it's plenty good enough for the job.

That's very interesting and I'd also like to see the source of this information. A Campyphile poster on another froum used to insist Campy used Grade 10 (or was it Grade 5 or maybe even Grade 3...) bearing balls and "hand matched" each and every set and they had to be used as a complete set. I was always suspicious of this claim and would like to know the truth.


It would be somewhat interesting to know, and certainly to debunk the hand matched nonsense, but does it really matter. As long as I was in the bike industry people always asked about what stuff was, rather than what it did. When I made cone wrenches and freewheel removers, I got all sorts of inquiries about the material they were made from. My answer was always that it didn't matter why or how a product did it's job and lasted, as long as it did both well.

I use the phrase " the proof of the pudding is in the eating" on the Chain-L site, and I used it years ago when selling tools, because I believe that that's the only issue a user needs to concern himself with. If I go to a restaurant where the food is consistently excellent, I don't query the chef about his recipes.

Back to Campy, given the extremely long service life of their bearings I don't need to know what grade balls they use, I already know that it's plenty good enough for the job.


I've heard the comments about 'hand matched' sets and matching lot numbers as well...who really knows? And yes, whatever it is that Campy used/uses is more than good enough for the job!!!

Here's a Campy document verifying grade 100 bearings, Campy didn't state this very often, I think I've only seen it 2 or 3 other times.

http://www.minortriad.com/campagbb.html

I've heard the comments about 'hand matched' sets and matching lot numbers as well...who really knows? And yes, whatever it is that Campy used/uses is more than good enough for the job!!!

Here's a Campy document verifying grade 100 bearings, Campy didn't state this very often, I think I've only seen it 2 or 3 other times.

http://www.minortriad.com/campagbb.html


The article in the link says the Campy balls had tolerances of 0.001mm. Converting to inches (1mm=0.0393"), that's right about 0.00004" for the tolerances.

According to Wikipedia, that puts the bearing grade at about 25, or maybe a little better.

http://en.wikipedia.org/wiki/Ball_%28bearing%29

The article in the link says the Campy balls had tolerances of 0.001mm. Converting to inches (1mm=0.0393"), that's right about 0.00004" for the tolerances.

According to Wikipedia, that puts the bearing grade at about 25, or maybe a little better.

http://en.wikipedia.org/wiki/Ball_%28bearing%29
Still a little inconclusive as there's several dimensions listed against any one grade, but I'll certainly agree that it does confirm that they're (were) more than good enough to do the job!

Here's a Campy document verifying grade 100 bearings, Campy didn't state this very often, I think I've only seen it 2 or 3 other times.

http://www.minortriad.com/campagbb.html
That's not quite what it shows. That Campy document claims their bearing balls are ground to .001 mm tolerances. But ball grades are based on inch tolerance numbers and 0.001 mm = 0.00004". The document it doesn't specify if the tolerance is for diameter or sphericity but a sphericity tolerance of 0.00004" is between Grade 50 (sphericity tolerances of 0.00005") and Grade 25 (sphericity tolerance of 0.000025") and if it's a diameter tolerance it puts their balls at about Grade 10 (diameter tolerance of 0.0005" which is the same for Grade 10 and Grade 5).

Agonizing over numbers aside, yes indeed Campy's bearing balls are more than good enough but so are Shimano's.

Here's a Campy document verifying grade 100 bearings, Campy didn't state this very often, I think I've only seen it 2 or 3 other times.



You didn't by any chance work on the mars orbiter a while back?

As the others have said, you made an error in translating metric to inch and (according to the literature) it seems that Campy does in fact use grade 25 (or possibly 10) balls.

Whew, I'm glad we got that straightened up.

BTW- while we're discussing balls, I remind you that lot tolerance is much tighter than overall tolerance, so it's important not to mix lots (lots of debate about that) because if you mix 2 lots of grade 25 balls you made one lot of grade 100. In practice one smaller ball in a bearing isn't a big deal, but on larger one is more serious. So for those who pay for grade 25, remember to discard the end of a lot before opening the new one.

Campy used to advertize grade 25 bearings at the same time I bought some grade 24 balls at a local bearing house in the united states at around 5 cents each. Bearing manufactures are constantly making small improvements they don't advertize. There used to be an exhibit in the Chicago museum that bounced ball bearings off two inclined planes to show how accurately they were made. Ceramic ball makers advertize they can be used without lubrication this is nice if you don't like to tear down hubs.

My friend at SKF asks that I correct this every time I see it.

Ball bearings are the complete assembly, including the inner and outer races, the seals and the balls. The balls themselves aren't bearings, they're just balls. If you wish you can call the bearing balls, so they're not confused with golf balls.

Excellent! Quite right - and I have been in the wrong for so many years. I really appreciate your pointing this out, but I am afraid I will find it hard to resist correcting others.

Excellent! Quite right - .... I am afraid I will find it hard to resist correcting others.

so we now have 2, it's a groundswell!!!!!

I guess I did botch it didn't I?

As always, I'll admit when screw up. It's happened before, it'll happen again.

I guess I did botch it didn't I?

.

But it's not like you made a multi-million dollar satellite crash into Mars. If rocket scientists can make a simple metric/imperial mistake, I guess we're all entitled.