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-   -   Cartridge BB Lubrication (http://www.bikeforums.net/bicycle-mechanics/936086-cartridge-bb-lubrication.html)

edotomato 02-28-14 09:26 AM

Cartridge BB Lubrication
 
My bikes been through some pretty grimy road conditions these past few months, and after stripping it, the BB was a bit gritty. I gave it a surface clean (I haven't removed it as I don't have a BB wrench) and it improved to a slightly sluggish feel, but not gritty. Would it be a good move to drip so oil into it?

rpenmanparker 02-28-14 09:32 AM

The only way to lubricate a cartridge BB is to unseal the bearings. Some folks talk about doing that, but I wouldn't. I would just replace it. What I don't understand is what you mean by stripping it, but not being able to remove it because of no BB tool. What does stripping it mean? Are we talking about a three-piece crank with a sealed cartridge BB as the middle piece, or an outboard bearing BB and a two-piece crank?

JerrySTL 02-28-14 09:35 AM

IMHO it would be a good time to replace it if it soon feels gritty again. Oil and grease don't mix all that well. Dripping oil into it could wash away the grease. You'd need to reapply oil frequently once you started using the oil.

Looigi 02-28-14 10:07 AM

I pull the outer seal off the bearing and clean and add grease as appropriate, then replace the seal. It's easy. Usually, I preemptively add grease, as many BB bearings have minimal grease to begin with. The added grease helps exclude water and grit.

Most press-fit BBs are bad in that they tend to funnel water and grit right to the inner edge of the outer seal and then work it through the lip of the seal into the bearing as the crank turns.

edotomato 02-28-14 10:54 AM

Quote:

Originally Posted by rpenmanparker (Post 16535063)
The only way to lubricate a cartridge BB is to unseal the bearings. Some folks talk about doing that, but I wouldn't. I would just replace it. What I don't understand is what you mean by stripping it, but not being able to remove it because of no BB tool. What does stripping it mean? Are we talking about a three-piece crank with a sealed cartridge BB as the middle piece, or an outboard bearing BB and a two-piece crank?

Sorry for the confusion, I meant stripped the bike. It's a 3 piece with a sealed cartridge.

edotomato 02-28-14 10:54 AM

Quote:

Originally Posted by JerrySTL (Post 16535079)
IMHO it would be a good time to replace it if it soon feels gritty again. Oil and grease don't mix all that well. Dripping oil into it could wash away the grease. You'd need to reapply oil frequently once you started using the oil.

This was what I feared.

edotomato 02-28-14 10:56 AM

Quote:

Originally Posted by Looigi (Post 16535224)
I pull the outer seal off the bearing and clean and add grease as appropriate, then replace the seal. It's easy. Usually, I preemptively add grease, as many BB bearings have minimal grease to begin with. The added grease helps exclude water and grit.

Most press-fit BBs are bad in that they tend to funnel water and grit right to the inner edge of the outer seal and then work it through the lip of the seal into the bearing as the crank turns.

Is this possible with out first removing the BB from the bike? I'll have little inspect in a moment.

rpenmanparker 02-28-14 11:05 AM

Quote:

Originally Posted by edotomato (Post 16535409)
Is this possible with out first removing the BB from the bike? I'll have little inspect in a moment.

On the three piece type you only have to remove both arms and the non-drive side cup. The arms often come off with just an 8 mm Allen wrench due to having a self extracting bolt. Sometimes take off the adjustable cup with a pin spanner. Then the sealed spindle/bearings just pull out in one piece. Otherwise you need a crank arm remover. But in any case you don't have to remove the fixed cup. If you are lucky to have that setup and have those tools, it is easy.

Leebo 02-28-14 02:00 PM

Cartridge BB's are a wear item. How old is it/ how many miles on it?

fietsbob 02-28-14 05:53 PM

UN shimano type bbs are disposable, and priced low.

Looigi 03-02-14 11:04 AM

Quote:

Originally Posted by Leebo (Post 16536075)
Cartridge BB's are a wear item. How old is it/ how many miles on it?

Indeed, and they wear less and last a lot longer with added grease. Bonus: Adding grease is easier, quicker and cheaper than replacing them.

As mentioned, they can easily be serviced in situ.

lopek77 03-02-14 11:27 AM

Just replace it. I use 3 different types of bottom brackets. I take everything apart to clean and grease the same day I hear first strange sounds coming from it. That include cleaning frame treads very well. Shimano BB can last a very long time. Sometimes is just luck, and sometimes is just maintaining it and keeping everything clean and dry. Expect 2000 or even more k happy miles from it. My bikes saw anything from salt water, sand, mud and everything in between. I "abuse" my bikes, and I love cheaper /they are not necessary low quality/ components. Easy and cheap to replace. My cycling fun never was and never will be spoiled by fear of braking/damaging my "high end", expensive components.

HillRider 03-02-14 11:30 AM

Quote:

Originally Posted by Looigi (Post 16541001)
Indeed, and they wear less and last a lot longer with added grease. Bonus: Adding grease is easier, quicker and cheaper than replacing them.

As mentioned, they can easily be serviced in situ.

How? With the exception of the Dura Ace version of the Octalink bb, all of the sealed cartridges I've seen are truly sealed and unserviceable without a can opener.

Leebo 03-03-14 08:29 AM

Quote:

Originally Posted by Looigi (Post 16541001)
Indeed, and they wear less and last a lot longer with added grease. Bonus: Adding grease is easier, quicker and cheaper than replacing them.

As mentioned, they can easily be serviced in situ.

As said before, they wear out. My last shimano un 54 had about 3 mm of play on the drive side. I just put in a new one for about $ 28.00. YRMV.

fietsbob 03-03-14 09:50 AM

IDK if you can pop off the seal discs and add grease ..
or have a type of BB that uses a replaceable pair of bearings.

cny-bikeman 03-03-14 09:53 AM

I would purchase a new unit and if practical add some grease to discourage reoccurrence of the problem on the new unit.

edotomato 03-04-14 09:30 AM

Quote:

Originally Posted by Looigi (Post 16535224)
I pull the outer seal off the bearing and clean and add grease as appropriate, then replace the seal. It's easy. Usually, I preemptively add grease, as many BB bearings have minimal grease to begin with. The added grease helps exclude water and grit.

Pull off outer seal: easy.
Add grease: easy- moving smooth once again!
Replace seal: yeah, there's no way that seal is going back in.


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