This was a house trip so the route is a variant and the speed was a fairly relaxed 23.96km/h.
Route:
View North West Cambridge Variant 3 in a larger map
Here is the Google Doc with all the stats:
http://spreadsheets.google.com/ccc?
key=0At0EKwdiLZmYdFg4Mk9fdHltdWlGeWpQTHMzM3RjU3c&hl=en_GB