Next to “So which is better? Shimano or Campy?” probably nothing else generates more tightly held personal views than how and with what to lube a chain. So with some reluctance, I throw a line of products in the ring for your consideration: Dumonde Tech Racing Oils, specifically their Bicycle Chain Lubes—Lite and Original. Maybe these are widely known to most of you, but they were new to me when I spotted them last summer. Three experienced bike mechanics recommended them highly, though each quickly added they required some care in how to use them. My experience in a nutshell: A little more picky and time consuming initially, but yielding superior performance, chain life, and ultimately taking less of your time over the life of the chain.
Dumonde technology was originally developed for high-revving Kart engines, and later found broad acceptance in the motorcycle world. It forms of bond with the metal at a micro level, effectively filling in minute imperfections in the inevitable bumps and holes in the material itself. In tech-speak, the Dumonde approach is a polymerization lubricant. Whew.
You must start with an absolutely clean chain. A thorough wash with a bike-specific citrus lube will do the job. (Dumonde makes one, too, though I think others will do nicely.) The chain must be completely dry before applying. ONE DROP at each pivot. Wow. That’s takes forever, huh? Well, actually under two minutes. But then you’re golden for many, many rides. Run the chain through a rag after each ride. (You should be doing this anyway, regardless of what lube you use.) How do you know when to re-apply? The chain becomes a little noisy. Put some more lube on. One drop per pivot.
The Original formula is more heavy duty, perhaps best on Cycle Cross or Off Road machines, but I would use it for my first application on your clean, new chain. Original will continue to work on your road bike, but I switched to Lite for reapplications. Lite is really just a somewhat more diluted form of the Original. After a really wet, grungy road bike ride, go back to Original once in a while.
I won’t set any expectations on how many miles you can expect on your Dumonde-lubed chain, because chain life also varies so much by chain brand and model, whether you spin more or push bigger gears, whether you climb a lot or not, and other factors. I’ll just say I’ve more than doubled my own typical miles per chain. The additional time to work drop by drop is more than compensated for by the reduction in how often you apply the lube. Did I mention the entire Dumonde line is bio-friendly?