Yesterday had a little problem. Going round a parking ballard at work, and having done it a thousand times before, the bike decided to lean and lie down.
Anyway, the seat leaned against the ballard and the bike just kind of leaned, so I managed to get it upright. However, when I moved it, I noticed this piece of rubber on the ground where the bike had leaned. It was warm so obviously it came off the bike.
I have no idea where it is from. I suppose it is a spacer of some sort.