I’ve tried several of the bicycle specialty chain lubes, and I haven’t been too happy with any of them. The last one I used, advertised to be ‘long-lasting’ and ‘repels water’, left my almost new chain rusted after one race in the rain at the beginning of August (Boston Tri). Here is what my chain looked like after I put the bike up on the stand and wiped everything down.
As you can see, just one sprint-distance race in the rain (and near the ocean with sea spray) turned the chain into one long line of rust. Using my Chain Breaker, I took the chain off, wiped off the last remaining lube, grit, and other road debris, then attacked the rust.
As using a wire brush and sandpaper is out of the question, there are a variety of commercial chemical products to remove rust. The most common on the left consists of a strong phosphoric acid-based solution which converts the soft, flaky rust into a harder, impervious coating. However, this is a little too strong for this case, and would result in coating that might bind between the links. The milder ‘CLR in the center is also an acid-based solution, mostly based on various organic acids such as citric and lactic (yes, the same lactic acid which builds up in your muscles), along with surfactants, which dissolves thin layers of gunk and surface rust. After cleaning the last of the oil and grease from the chain using the IPA (isopropyl alcohol, 91%) , I let it soak a bit with occasional agitation.
After a bit, the last of the rust was gone, leaving a clean chain in a dirty, rusty water bath. Removing the chain with gloves, I rinsed the chain with cold water and then immediately with the IPA to remove last traces of water. Wiping down the chain with clean paper towels, I hung it to finish drying.
Meantime, I set up a double-boiler and melted one block (out of the four-block pack) of the paraffin wax I recommended previously. After the wax had melted and the water under was gently boiling (don’t let the water boil over!), I put the chain in to soak.
The chain bubbled a bit as the paraffin soaked into the links, and then slowly stopped. After allowing it to soak a bit more, I fished the chain out, and hung it to cool.
After the chain cooled, and the paraffin hardened, I had to flex the chain a bit to get the individual links moving. Once the chain was moving somewhat freely, I checked it against the chain wear gauge.
As the gauge showed only a minor amount of wear (perhaps I should have checked it before cleaning and waxing), I mounted it back on the bike, and spun the crank and shifted until the chain moved smoothly through the full range of the derailers.
Result: Almost new chain, dry lubed, for just a few pennies, which will not attract sand and grit. It worked well for Cranberry Olympic, and what do you know, the old, tried and true method appears to give the best results according to Velo News, Sheldon Brown, and even testing from a laboratory dedicated to cycling. Take that, overpriced, fancy lubes.