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For this bottom bracket type I am not sure you can take the bearings out to lube them. How do I get grease in there. Also how do I get the old grease out? Does it even matter?

Sram Apex Bottom Bracket

I found this video (External Bottom Bracket Cup Bearing Removal) where someone removes the bottom bracket bearing cup, but they never showed the bearings.

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4 Answers 4

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Official SRAM manual describes the cleaning process well.

An excerpt from it:

SRAM manual excerpt

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    I gave this one the answer since it quoted the source with a link to the manual. There is still value in @zenbike's answer since it goes into the practicalities of the repair.
    – Chris Belsole
    Commented May 16, 2018 at 14:42
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SRAM GXP bottom brackets can be user serviced, but it is usually unnecessary.

To service your BB bearings, first remove the crank arms. Then place your thumb in the BB spindle hole, and bend the joint enough that your knuckle makes firm contact around the entire ring surface of the spindle hole. Pull outward using fairly firm pressure, and if necessary, rock your thumb side to side. This will pull free the outer, plastic shield, and expose the inner rubber bearing seals.

Then take a scalpel, or a sharp awl, and use the tip to gently pry up the edge of the bearing seal. You may need to lift it at more than one area around the edge, but it should pop free with a little force.

Once the seal is removed, clean and degrease the exposed bearings, replace the grease with fresh grease, then replace the seals. Repeat on the bearing on the opposite side of the BB.

One word of warning: while this is possible, and not likely to cause any issues, it is not intended by the manufacturer, and will not be covered under warranty, should you damage the BB in the process.

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    I think you meant "regrease" instead of "degrease" here? You certainly didn't mean to reassemble the unit with no grease inside.
    – John Zwinck
    Commented Mar 19, 2016 at 0:56
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    I did actually mean degrease, but forgot to specify the replacement of grease. :) Oops! Thanks for pointing it out.
    – zenbike
    Commented Mar 20, 2016 at 2:22
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    Citing long experience as a professional mechanic: SRAM bottom brackets do not last particularly long, especially in very muddy/wet conditions. Repeating the above process several times will eventually wear out the bearing seal seat and begin to allow water and grit in. If you begin to feel roughness in the bearings, even after re-greasing them, it's fairly inexpensive to replace them ( $30, plus the $15 tool).
    – JonR
    Commented Mar 23, 2016 at 3:33
  • Fully agree. Service only works for so long.
    – zenbike
    Commented Mar 26, 2016 at 16:48
  • @zenbike How would you degrease a bearing "in situ"? The only methods of degreasing that I'm aware of would require uninstalling the bearing.
    – jayhendren
    Commented Aug 19, 2018 at 5:10
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These bottom brackets use sealed bearings, which are in a metal casing. Unlike cartridge bearings, the bearings are not exposed and are sealed from the outside environment.

There are some bottom brackets that are are meant to be user serviced, like the chris king bottom bracket, but others may be much more difficult without specialized tools, while lower end ones may be expected to simply be replaced.

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I have press fit road GXP SRAM bottom bracket.

GXP Truative SRAM BB

I found out it's worth greasing rubber seals (red on the picture) covering bearings every 2000 km or at least before wet season. I don't take bearings seals out, just put some grease under red seals to keep as much water away from bearings. Without lubrication this BB lasts 8000 km for me.

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