Ceramic over Steel Bearings - worth it?

simon johnson
simon johnson Posts: 1,064
edited September 2010 in Workshop
I'm about to replace my freehub in which the ceramic bearings are shot, just not sure if it's really worth paying £85 rather than £45 for ceramic?? I did find this interesting article on Park Tools' site

http://www.parktool.com/repair/readhowto.asp?id=151


Would be interested in people's opinions as I'm going to order tomorrow.
Where\'s me jumper?

Comments

  • crankycrank
    crankycrank Posts: 1,830
    As stated in the Park Tools link:

    "The ceramic bearing has found uses in industrial applications where there is high speed, high load, and, consequently, high temperature. Bicycle riding simply does not result in high load, speed or temperature. A bike moving at 80 kilometers per hour (about 50 mph), will have hubs that rotate about 11 revolutions per second. An engine crank shaft, however, may turn at over 100 revolutions per second."

    This is pretty much what I've heard from reading up on ceramics and I used to race motorbikes where ceramic bearings were sometimes used in 15,000rpm, 180 horespower engines by engine builders with wealthy customers. Most in the racing business felt that for wheel bearings and such, ceramics were overkill unless you had someone else's money being thrown at you to spend.
  • simon johnson
    simon johnson Posts: 1,064
    I think that the state of my current bearings should more than answer my own question here - disintegrated. Though I think that the bearings were ill-sealed.

    Yeah, I'm going steel at half the price.....I'm also changing my carbon bars and stem for alloy: a multiple regression then!
    Where\'s me jumper?
  • Nigel Bennett
    Nigel Bennett Posts: 653
    One theory I heard was that you only need one ceramic ball in a set. Allegedly the ceramic ball is able to "repair" any damage caused to the races by the steel balls, and the set-up is supposed to outlast an all-steel setup.

    I suppose the quality of the sealing and the environment in which the bearing is run will be the major consideration.

    Unless you do a comparative test, you'll never know for sure!
  • keef66
    keef66 Posts: 13,123
    "15,000rpm, 180 horespower engines"

    I think you left out the w?
  • crankycrank
    crankycrank Posts: 1,830
    keef66 wrote:
    "15,000rpm, 180 horespower engines"

    I think you left out the w?

    Ooops. Well, that would be expensive then. :shock:
  • moonshine
    moonshine Posts: 1,021
    what about steel vs stainless steel bearings?

    my fixed wheel rear bearings have 60002 sealed bearings...

    i can get steel replacements for £3.00 each http://simplybearings.co.uk/shop/p943/60002RSR+Rubber+Sealed+Deep+Groove+Ball+Bearing+10x26x8mm/product_info.html
    or , or Stainless Steel for £8.00 http://simplybearings.co.uk/shop/p55045/W60002RSR+Stainless+Rubber+Sealed+Deep+Groove+Ball+Bearing+10x26x8mm/product_info.html

    i went for stainless.... hoepfully they will be longerlasting than the regular berings
  • crankycrank
    crankycrank Posts: 1,830
    Stainless are generally softer than steel and will not last as long. As long as steel bearings are properly greased there won't be any problem with corrosion. Since you already purchased the stainless, don't worry they'll be fine. Install, ride, enjoy. Google some info on bearings and you'll find hardness ratings, advantages-disadvantages of stainless, steel and ceramic.
  • moonshine
    moonshine Posts: 1,021
    crankycrank wrote:
    Stainless are generally softer than steel and will not last as long. As long as steel bearings are properly greased there won't be any problem with corrosion. Since you already purchased the stainless, don't worry they'll be fine. Install, ride, enjoy. Google some info on bearings and you'll find hardness ratings, advantages-disadvantages of stainless, steel and ceramic.

    interesting.... they are not dear and i've ordered stainless... i'll see how they go and order carbon steel next time... even cheaper!

    Thanks..

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