Originally Posted by Pete Hamer
I agree about the adjustment causing more damage.
The disastrous result can only be one thing; damage to the bearing unit. It entirely possible that you and I have seen the disastrous result of using the wrong grease but didn't recognize it for what it was. On the other hand I have seen the result of using bicycle specific grease and good maintenence practices, the hubs last for many years and tens of thousands of miles. The problem is that I have no way of knowing if the "disastrous result" (bearing damage) that I do see are from the "wrong" grease or someting else. I have seen a lot of ruined hub bearings but I never know what grease was in them, how well they were adjusted, how long it was since their last re-pack, if there was moisture contamination, etc. The only anecdotal evidence of using the wrong grease (other than bearing and surface damage) that I have heard of is that the grease will get dry, the bearings will displace the grease (probably just the thickener without oil) to the side and the bearing will be running on a dry track.
But also don't forget bearing and race quality in your equation.
Anyway, I aim to get over all this in future by using only sealed bearings... but, I just realised... most sealed bearings used on bicycles are the generic types used in car alternators, ceiling fans and various industrial electric motors and other applications... and they *don't* use bicycle-specific grease.
Sorry, Pete, I just had to point out that little tidbit. Maybe a quick email to Shimano to find out the type of grease they use in their sealed BB and wheel bearings might put the issue to rest.
(Of course, having said that, you'll probably get a reply along the lines of "we use on our sealed bearings grease plating, a patented Shimano process that we also use in fishing reels". I doubt it, though.
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