Weird problem, I think.
 

Hey,
Got a weird happening that I can't figure out and wondering if anyone has seen it before.
When I remove, clean and re-lube my chain (pc-850) there is always some roughness in the middle gears on the cassette, the others are fine. There are about 2500 miles on the chain and cassette. This goes away after about 50 miles and then everything runs smooth as silk until next re-lube, about 300 miles. I noticed it after I switched from a home brew chain lube to a bike specific lube from Schwinn. The first time I thought I had somehow messed up the derailleur adjustments and spend some time screwing with them but had no success. The last 2 times I just ignored the issue and like I mentioned it cleared itself up. Any ideas?

What do you use to clean your chain and are you certain that you have removed it before you apply the chain lube?

+1,

The most common mistake folks make cleaning chains is failing to dry them completely inside and out. Looking dry or wiping the outside doesn't count, since the cleaning fluid remains trapped inside the chain by capillary action. (picture water that's run under a glass table top).

The liquid already inside, fills the available spaces, so the newly applied lube sits on thee outside, where you probably wipe much of it off immediately. So you're now running a chain that's lubed with solvent rather than lubricant, magnifying the noise of running on slightly worn sprockets. Eventually the solvent dries and the lube migrates in, or the movement works it in maixing with the solvent, and your, now lubed chain, runs quiet again until the next time you screw it up.

+1 - The later lack of noise is the chain finally getting the lube where it's needed.

You guys could be right about the drying time. I use kerosene as the cleaner and hang the chain for about an hour while I'm cleaning the sprockets, jockey wheels, chain rings and the rest of the bike. Next time I'll give it a longer drying time. Thanks for the advice.

Kerosene will not dry completely at room temps unless you give it a tremendously long time. Put your chain in a warm place (not your oven) such as a car parked in the sun with one window cracked open 1/2" for a few hours, or do a final rinse or two with naphtha or mineral spirits, which will dry completely at room temps in an hour or two.

I wasn't aware of that. I've been thinking of switching to mineral spirits.