Despite the gorgeous weather as of late, my bike is spending a lot of the time parked up in the garage as i'm away from home. When I come back at the weekend to ride her, my chain keeps rusting. I have always cleaned my chain every month or 500 miles and re-lube it with a heavy weight mineral oil which normally does the job quite nicely, and have done it for years. However when I leave her still for a week or two at a time, it keeps rusting over which is really annoying. What does everyone use on their chains, and does anyone have an tips to keep their chain in tip top condition?