Hello, I wonder if anyone can help. I used my Wisper for the 1st time in several months today - it was great to get back out on the road- and my only problem was that although my speedometer was showing the time of day it wasn't showing the speed. I assume that there are sensors of some sort on the wheel(s) which transmit the info back to the wireless display unit on the handlebars but I'm useless at technical stuff and so any suggestions as to what the problem might be would be very welcome. Thanks