Tyres birthday - how do I find it?

[ajw_888]

I've done a few searches here and the web, I am wanting to find out the age of a couple of slicks I have. The came with the bike and are hardly used but could potentially be quite old.

Does anyone have a link or info on this.

michelin slicks (the michelin site info doesn't match what I found on the tyre) S1845A and S1246A

[Kickaha]

Car article but it applies to bike tyres as well
http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=11

the numbers you're looking at aren't the date codes

[MSTRS]

On one sidewall should be an elongated 'circle', with 4 numbers in it. The first 2 are the week of the year, and the second 2 are the year of manufacture.
ie...One of mine has 0409. It was made in the last week of January, 2009.