Here is my test info on purple extreme.
Playing around with chain lube is cheaper then other bike parts. And it is pretty easy.
I always cleaned the chain with acetone between lubes.
http://www.purpleextreme.com/
this works very well in dry weather. I get about 400 miles out of it before I hear any chain squeak. Thatís 10 rides a week for 10 miles. But I found to get it to be really effective it needs a lot of drying time. A week is good. I apply it to the chain move the chain around and hang it up for a week. After a couple days I wipe any excess off and let it finish drying.
This gives a nice quiet chain and a dry chain. It hardly gets any black at all on it. One of the longest lasting but far cleaner lubes I have used.
But the two times I tested it in the rain were not real accurate. The first time I got hit by a car and the bike replaced. The second the chain only had a couple days to dry. So I should know soon as it usually rains often here in Portland.
But for dry weather this lube is about the best I have found.
If you can handle a little black there are a couple other really nice lubes too. Voo dew is really good and does not need the drying time and durmond is pretty good too and if you reapply it I can get 6 or so rain rides out of it.
I have a new lube from Honda for motorcycle chains a friend says works very well. I will test it next.