Saw this: http://www.redline360.com/garage/wp-content/uploads/2012/12/donk-hummer-wagon-wheels.jpg

Sweet ride – It just goes to prove that inspiration can come from anywhere. Wooden tires inspiring a ‘time machine’ story is awesome!

A silly consequence of time travel, but illustrative nonetheless. Fun little entry into the challenge.

Well, this is so far the entry that keeps closest to the challenge, so points for that.

On the other hand, I don’t understand what’s going on. What could a time-traveller possibly do to inadvently prevent the discovery of rubber? If I have to research rubber to understand your story, then I think you’ve bitten off more rubber than your story can chew.

I’m also not getting much of a sense of character. You mention the sense of embarrassment, but nothing that makes the character stand out as interesting.

Finally, if rubber is unknown in this reality, would it not also be unknown to the time machine owner?