Originally Posted by
lightspree
Some of the qualities that make a real difference, for me are:
(1) Does the grease harden over time more quickly or less quickly?
(2) Does it leave more hardened residue or less hardened residue, after drying and thickening over time? (Polyurea-based and synthetic greases are much better than lithium-base and calcium sulfonate-base greases, and probably also aluminum-base greases, in this area.)
(3) Does it extend the life of bearings and other components, compared to other greases?
(4) How long does the grease last -- how long does it do its job well?
(5) Is it water resistant (both to washout and to absorption)?
(6) Does it provide a high level of corrosion protection?
(7) For bikes kept indoors, is it low odor?
Just about any modern grease hits all these points. While "axle grease" from 20 or 30 years ago might have hardened over time, that is (mostly) a thing of the past. I regularly see bikes from the 1980s at my local co-op with grape jelly where the grease used to be but bikes from the 1990s seldom suffer from that problem.
As to extending life of bearings, it's a matter of how you define "extending life". Any grease is better than none, of course. But I highly doubt that using product A vs product B is going to have a significant effect...or even measurable effect... on the life of a bearing in a lightly loaded vehicle like a bicycle.
In other words, it probably doesn't matter what you use.
Originally Posted by
lightspree
There are some others too. Greases that are less toxic - both in terms of personal exposure, and in terms of ecotoxicity (including manufacture and disposal) - are preferable.
Super Lube seems like great stuff in many ways. It's non-toxic and even food-safe (for incidental exposure), and it gets many rave reviews. The thixotropic thinning during use is a potential issue though, at least in some applications.
https://www.amazon.com/gp/product/B0...=ATVPDKIKX0DER
While worrying about the environment is a worthy goal, the amount of grease that a bicycle uses is so little that even a highly toxic material would used in such extremely small quantities as to be negligible compared to other forms of transportation. And, if you are going to go so far as to worry about "ecotoxicity" at every level from manufacture to disposal, no grease... or even modern manufactured item...is completely nontoxic. Your preferred grease, for example, contains petroleum distillates which are anything but "nontoxic" to make. There are a lot of steps in the manufacture of petroleum distillates that are not just toxic but highly toxic.
As for disposal, your preferred grease contains fluorinated compounds which are nontoxic as long as they are kept below about 200°C. Above the temperature, the material decomposes into various fluorinated monomeric compounds that are very toxic. Don't burn it.
Additionally, making fluorinated compounds isn't a benign process either. The materials use for its manufacture are highly toxic.
Bottom line, however, is that it's not something that we bicyclists should be terribly concerned about. We use so little of
any resource that we shouldn't feel bad about using a little bit of grease.