Just to put some of the posts about average speed in perspective. Ride of the day yesterday for me was Mary Dawson of the Teeside RC who posted a time of 1-23-20 an average speed of a fraction under 18 mph. This amazing lady is 83 years of age.
Here is a link to the time trialling forum with an opening post by Jane who incredibly was able to write this somehow from her hospital bed. We have sent her a message but I am sure that all on here who read this would also want to send their best wishes, you don't have to know a fellow cyclist.
http://www.timetriallingforum.co.uk/index.php?showtopic=69360