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...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/...ll+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.

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

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.

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.

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....

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.

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

+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.

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

Campagnolo's very own literature!!!!!

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