Rust
 

I recently bought a cheap used department store road bike. I wanted to get into the sport for fitness but cannot afford to spend a lot of $. So far I love it and it works great for what I need it for. My only issue is that the previous owner did not care for it very well and there is a fair amount of rust present on the cassette and chain. The chain I can deal with but what is the best way for me to care for the cassette? Don't really care about aesthetics just want to stop the problem from getting worse and affecting the performance of the bike. Also what sort of lubricant should I be using?

Thanks.

Use a wire or stiff bristle brush to knock the loose rust off the cogs. There are lots of good chain lubes out there: Pedro's, Chain-L, even chain saw oil in a pinch. Avoid leaving the bike out in the rain and it won't rust again.

The cassette is like railroad tracks in that use keeps the working surfaces rust free. The rest barely matters, since there's nearly zero chance that it'll rust through. There's no need to remove the rust, and you can apply some oil to slow or arrest the process. If you do nothing except ride it, chin oil will migrate and protect it anyway.

I would scrape or brush off the cog rust where the chain will mesh on the teeth. I wouldn't spend much time doing it, just enough so that the chain rubs off less remaining rust. Either way I would soon remove the chain and give it a thorough cleaning to flush away the rust filled lube.

Interesting story- Years ago I had a 20" 3 speed folding bike. I had loaned it to a friend a year before and got it back with a very rusty chain, almost enough to be not useable. But I was able to free up all the links so reinstalled it then re tensioned the chain. Lubed then rode the bike work a few times. After a couple of weeks I noticed the chain was quite loose. The wheel was in the same location in the drop out as before. But I also noticed that the chain was much more freely turning too. My theory was that the rust that coated the chain link interiors got scraped/rubbed off then carried away as a slurry of oil and rust dust. As the rust left the chain link interior the roller and other parts develop more play and the chain "grows" in length. When I cleaned the chain the solvent run off was very brown. The, now cleaned, chain felt loose and free in the links. Reinstalled it, again re tensioned the chain, lube and ride. The chain proved to be stable in it's now far more rust free state. The bike ran smoothly and the chain remained well tensioned. Andy.

Thanks guys! Scrub it, lube it, ride it and clean it. Got it!