I live in Phoenix, Arizona USA. It can reach temperatures of 115 degrees F or more in the summer months. Thankfully I have not yet had this speedo problem, but I am very concerned about it. My bike is a fairly early model built in December of '09, so if early speedos were defective I would think that I must have one of these, but I pray that I don't.
My bike is also a December 09 build, and the speedo problem just manifested itself for the first time at 6000 miles. Replaced under warranty without issue by Triumph. We'll see how this one holds up to a hot Florida summer's worth of riding.