The first time I saw a can of Boeshield T-9 in a bike shop I was a bit surprised because I had several cans of it in my garage but had never even thought of using it on my bikes. I live between Chicago and Milwaukee and all of my woodworking tools are stored in an unheated garage, so to keep them from rusting I spray them with Boeshield T-9. I also use it on my snow-blower (and it got a tremendous workout this past winter). My favorite use for it had always been on my table saw—not only did it keep the surface from rusting, but it provided an extremely slick surface for the wood to slide over.
Boeshield T-9 was developed by The Boeing Company (you know, the folks who make those pretty planes). This product has a solvent and paraffin wax base and uses neither Silicone or Teflon. The solvent penetrates deep through other lubricants, but I would recommend you clean the surface first before you use Boeshield T-9 if for no other reason than it looks better that way. Boeshield T-9 dries quickly, but it is best to let it dry for a couple of hours before wiping off the excess. This will leave you with an incredible barrier against rain, mud, snow, ice, salt and road grime. The bike I reserve for riding in the rain is coated with this stuff! My winter bike is fed a steady diet of ice and road salt, but it still looks great because of the protection Boeshield T-9 provides.
Boeshield T-9 is suitable for use on derailleurs, brake cables, pivot points and the chain. If you have a metal bike frame and ride in either snow or rain I would suggest you spray Boeshield T-9 on the entire frame (inside and out). This product will not harm paints, plastics, or rubber.
Boeshield T-9 is available in a variety of sizes, from one ounce bottles up to gallon containers, and in aerosol cans. I prefer the aerosol because it is so easy to use (on the bike and everywhere else). Regardless of what form you buy it in, Boeshield T-9 has exactly the same formula. The 12-ounce aerosol can retails for $18, but you can get it for around $14 from Amazon.com. You can also find it in a lot of retail stores, such as Sears, R.E.I., Trek, Camping World and Woodcraft.