Are the Bottom bracket races threaded in?

Discussion in 'Motorized Bicycle General Discussion' started by Patr1ck, Jun 21, 2010.

  1. Patr1ck

    Patr1ck New Member

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    Are the bottom bracket bearing races threaded or pressed in to their housing? Im looking for a way to run sealed bearings this is why Im curious. Do they make sealed bearings for a 1 piece crank?

    Thanks,
    Pat
     
    #1 Patr1ck, Jun 21, 2010
    Last edited: Jun 21, 2010
  2. wildemere

    wildemere New Member

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    Low end bikes usually have a threaded BB with loose balls.

    Only high end and racing bikes have a "cartridge" BB with sealed bearings. The end play is still adjusted with a threaded lock ring.

    1 piece steel cranks are the lowest option the scheme of quality bike parts.
     
  3. Patr1ck

    Patr1ck New Member

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    Do the races thread into the big hole at the bottom of the bike or are they pounded in and out? What is the name of that big hole that all the crank pieces go into?

    Pat
     
  4. wildemere

    wildemere New Member

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    Its called the bottom bracket or BB. it is threaded, no pounding is allowed or required.
     
  5. Patr1ck

    Patr1ck New Member

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    What is the shaft that goes through it when you have a 3 piece crank? the crankshaft? How do I remove those bearing races? There isnt anything to hold onto to twist them.

    Thanks,
    Pat
     
  6. BarelyAWake

    BarelyAWake New Member

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    My bottom bracket had the bearing cups/races pressed in (if there's nothing to twist or "hold on to" yers is prolly jus' pressed in too) & if you wish to convert to a three piece crankset (cartage or bearing) it's easy 'nuff w/this: Bottom Bracket Adapters

    [​IMG]
     
    #6 BarelyAWake, Jun 21, 2010
    Last edited: Jun 21, 2010
  7. bairdco

    bairdco a guy who makes cool bikes

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    the larger bottom bracket for one piece cranks is called a "cup and cone" system, with pressed in cups that hold the bearings. you can beat them out with a hammer and a wooden dowel. you don't want to use a punch or a screwdriver because you don't want to damage the cups, 'cause that will mess up your bearings. to install cups, put a piece of wood like a 2x4 over the cup and whack it with a hammer a few times till it seats.

    they can be converted to a sealed bearing system like the link BA posted above, and then you can put 3 piece cranks on.

    the smaller bottom brackets have a sealed bearing set up, and can only be used with 3 piece cranks. these normally need a crank-puller to remove the cranks, and sometimes special tools are needed to remove the bottom bracket assembly itself.

    if you do a search for "bottom bracket removal" you'll find a few sites that will walk you through it, depending on which type you have.
     
  8. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    bairco for president.
     
  9. bairdco

    bairdco a guy who makes cool bikes

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    too many past indescretions, joe.

    and pat, the bearing races are called "cups," the "big hole at the bottom of the bike" is often called a "crank hanger," and the shaft on a 3 piece crank is a "spindle."

    extra credit if you can use them all in a sentence.:}
     
  10. Kevlarr

    Kevlarr New Member

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    My wife got a hold of my crank hanger and tried to hit me in the spindle but luckily I was wearing my cups. :D
     
  11. 2door

    2door Moderator
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    >>>>>>>>>>>>>>>>>>>>>>> :)

    Tom
     
  12. bairdco

    bairdco a guy who makes cool bikes

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    nice one, kevlarr:)
     

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