Bicycle Mechanics - Replace bottom bracket cup & bearings?

I've got a bad bottom bracket cup & the bearings that go with it. The bike is Nishiki Olympic road bike, I think around '88 or '89 or something. The cup has a rubber piece that's bad as well, I'm assuming it keeps the grease from coming out of the cup...?

Anyways... how do I go about replacing the cup, bearings & rubber piece? Should I just buy a whole new bottom bracket 'kit'? The fixed cup looks good and the bearings are good.

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Standard ISO/English Size 1.37" x 24 TPI BB022

Look at the Harris site and see if it loks like yours.

http://sheldonbrown.com/harris/bottombrackets.html

You can get a cartridge pretty cheap.
http://www.amazon.com/Shimano-Tapered-Spindle-Bicycle-Bracket/dp/B001T4W7PC

You still haven't said what condition the spindle is in.

That said, usually the fixed cup (IME) is the bad one. If you have a friend that wrenches on bikes, maybe they have an adjustable cup in the parts pile.

One option is to put in a new shimano cartridge BB.
Replacement cups on the Harris site cost almost as much.

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looks like the bearings bit into the adjustable cup. What do the insides of the fixed cup look like?

Spindle appears to be ok.

The frame is not with me right now, a buddy had to remove the stem for me 'cause it was frozen pretty bad, which has the fixed side cup... so not sure what shape that's in. Will have to wait till Monday night to check it out. I think I'll probably just replace the entire thing if it's as cheap as Bill's link is. How do I measure the spindle?

Spindle appears to be ok.

The frame is not with me right now, a buddy had to remove the stem for me 'cause it was frozen pretty bad, which has the fixed side cup... so not sure what shape that's in. Will have to wait till Monday night to check it out. I think I'll probably just replace the entire thing if it's as cheap as Bill's link is. How do I measure the spindle?

http://sheldonbrown.com/bbsize.html

The fixed cup is the one screwed into the drive (right) side of the BB; the adjustable cup is on the non-drive (left) side. It's that way so you can get at it to adjust bearing tension with the crank arm off while the chain is in place on the other side (if it were the other way around you'd have to take off the chain and chainwheel crank). The spindle length is the distance in mm between the left and right spindle bearing races (surfaces).

...The spindle length is the distance in mm between the left and right spindle bearing races (surfaces).


On a 68MM shell width, that distance is 52MM!
It's the "other" distance that counts.

To determine the size cartridge you need, you'll have to read the size code from the spindle.
It'll likely be something like 3-P, 3-S etc.
The 3 means a 68MM shell width.
The LETTER is the code for the spindle dimensions.
SOME spindles are symmetrical and others will have one end longer than the other.
IF you spindle is NOT symmetrical, you have to know if the DS had the long or short end. THAT is what will ultimately determine the needed cartridge length.
You may have to reinstall the spindle and eyeball the chain line to make sure which is the correct side if you didn't observe the orientation when it came out.
(I already did that myself today)

IF you have the spindle, report back what the code is and worst case (we hope), we can narrow the choice down to 2 cartridge lengths. Maybe we'll get lucky and you have a symmetrical spindle and there will only be one result.

how do I go about replacing the cup, bearings & rubber piece? Should I just buy a whole new bottom bracket 'kit'? The fixed cup looks good and the bearings are good.

If you can find a comparable cup with the seal, go for it. I've never seen the seals sold separately from the cups, but I may be wrong. Otherwise, you may have to buy both cups to get what you want.

BTW, the seal is not strictly necessary but acts to keep contamination out of the grease, rather than keeping grease in the cup. Since the fixed cup is ok, and that's the cup that determines chainline placement, you might be able to scrounge a replacement adjustable cup (with or without a seal) that will work with your spindle and shell width.

And replace the bearings anyway, as a matter of policy.

If you can find a comparable cup with the seal, go for it. I've never seen the seals sold separately from the cups, but I may be wrong. Otherwise, you may have to buy both cups to get what you want.

BTW, the seal is not strictly necessary but acts to keep contamination out of the grease, rather than keeping grease in the cup. Since the fixed cup is ok, and that's the cup that determines chainline placement, you might be able to scrounge a replacement adjustable cup (with or without a seal) that will work with your spindle and shell width.

And replace the bearings anyway, as a matter of policy.

Quick/easy question regarding the bearings: the bike had the bearings in a metal cage/cartridge. 9 bearings in it, 1/4" diameter. I can simply get bearings to replace it right? Do I need to find bearings in a metal cartridge? If I don't need the metal part, I'm guessing 9 won't do it, I'll probably need 10 or 11 to replace the 9?

Thanks for the help!

Quick/easy question regarding the bearings: the bike had the bearings in a metal cage/cartridge. 9 bearings in it, 1/4" diameter. I can simply get bearings to replace it right? Do I need to find bearings in a metal cartridge? If I don't need the metal part, I'm guessing 9 won't do it, I'll probably need 10 or 11 to replace the 9?

Thanks for the help!

yes, you can just buy individual bearings. no you don't need to "find bearings in metal cartridge(s)", you can just buy individual bearings. they can be found at most hardware stores.

yes you will need more than there are in the caged version. how many more? don't know. i usually put as many as fit then remove one or two depending on how small they are.

you may be able to buy a new caged set at your LBS and they are to be recommended over loose ball bearings. holding a frame in one hand and trying to position greased ball bearings into the drive-side cup from the other side without losing them in the chainstay tubes, or up the down tube or down the seat tube can be frustrating to say the least. and when you do (remember they are greased) they don't want to come back out so easily, however the ones you have already managed to insert successfully do. :crash:

Quick/easy question regarding the bearings: the bike had the bearings in a metal cage/cartridge. 9 bearings in it, 1/4" diameter. I can simply get bearings to replace it right? Do I need to find bearings in a metal cartridge? If I don't need the metal part, I'm guessing 9 won't do it, I'll probably need 10 or 11 to replace the 9?

Thanks for the help!

Common practice to replaced caged bearings with loose, but you'll probably need 11 to replaced the 6 caged. Usual method is to fill the reace completely with bearings, then remove 1. Take the caged bearings to your lbs to make sure you get the correct size bearings. And if you're like me, but at least 5 or 6 extras to replace the ones you drop on the floor and which will promptly roll to some unknwon or unreachable destination/

Twenty two 1/4" bearings is what you need.

I always remove the fixed cup so I can inspect it more thoroughly.

IF you don't, I find it easier to use a LOT of grease on the spindle race and install the bearings on that.
Then carefully insert the spindle. (ELEVEN 1/4" per side)