Lot's of stuff on the interweb about this speedo error. Basically they all state that motorcycles are set at 6-10% over actual speed, while the odo's are very accurate. Accuracy for the odo's were/are needed for warranty and maintenance purposes, but optimistic speedos were there to eliminate the possibility of law suit clams that the speedos were slow and causing folks to be ticketed, for speed, when they thought they were traveling the legal speed.
The worst I have owned in the past decade was a Triumph T100, that was a consistent 10% off to the plus side at all speeds. Guess that was to make owners believe they were doing the TON, which wasn't easy to get to, when they were really at 90MPH. Most of my bikes read 33 at 35 MPH radar speed readers, in my town. If that % is consistent, that would be around 4MPH at 60-70. I stick to that formula, and have never been bothered by the po-lice when riding for speeding.
Also read for years that GPS readings are only fully accurate if you can travel on an unobstructed road for several miles, at a concistant speed, allowing the GPS and the satellite enough time to sync properly. No scientist here, just repeating what I have heard for many years. tomp
Funny, but it was the fact that the '16 was not improved, as we hoped, that I bought the '11 last week. No reason to waste money on the same bike, regardless of model date. tp
