rpenmanparker 

Lot's of folks talk about doing this, but I have always been skeptical about it. I have been concerned about damaging the seals getting them out and having them not seal properly when they are reinstalled. And although this has been mentioned fairly routinely, I hadn't ever seen a demonstration of it. But trying to keep an open mind, I found this video pretty easily. Looks simple enough. I don't suppose the degreasing step is always necessary. Who knows, I may even try it!

\https://www.youtube.com/watch?v=5Px3n_DzGeE

demoncyclist

The degreasing step is necessary- just like cleaning loose bearings, you need to remove the contaminated grease and physically inspect the surfaces. If you aren't going to do that, you may as well not bother opening them up and simply replace the cartridges.

rpenmanparker 

I don't doubt what you say, but my experience with degreaser followed by water has been so horrendous (messy, ineffective at removing the grease, needing some elbow grease, etc), I just shudder to start that whole process. But I agree it is necessary. I wonder if spraying WD40 in the bearing with a bowl underneath to catch it wouldn't be a better plan. Then air drying. Assuming proper fire precautions, of course.

demoncyclist

Used and disposed of properly, any solvent is as good as any other as far as I am concerned- personal preference.

HillRider

Using water based degreasers is fraught with problems of rinsing out the detergent and then thoroughly getting rid of the water. I avoid them for anything but exterior surfaces.

Why use WD-40, when plain Kerosene or OMS (odorless mineral spirits) are a lot cheaper and basically identical to WD-40 without the small amount of lube. Soak the old grease out with Kerosene or OMS, air dry and repack with suitable grease. BTW, if you buy OMS, get the real thing, NOT the new "Green" OMS which is a water based solvent.

rpenmanparker 

Yes, OMS is suitable. I was thinking the aerosol spray action would be helpful. Thanks.

Jed19

Same as HillRider in post #5 . I never ever mess with water based degreasers on sensitive areas of the bike. OMS for me.

NatUp

And that's why people use cartridge bearings. Disassembling, degreasing, inspecting, re-greasing and reassembling really is a pain, a process at which one might shudder, as you say. Just pop out those old cartridge bearings, pop in new ones and ride away with the knowledge that -- and this is the really important part -- you can't accidentally go too long without overhauling your bearings and ruin your hubs/bottom bracket/headset/etc.