One last note and then some final thoughts, my speedo is dead on with my SatNav. Now the Crosstourer Forum states that there is a 10% error in the speedo. So I am curious as to why mine is dead on. Which I think is great. But I am thinking that hidden under the covers somewhere a SpeedoHealer is sitting. But since I got the bike through a dealer I have no PO contact info.
Nice write-up. I fancy taking a look.
Re the comment - ignore what other people say about speedos being 10% out. Speedos, like all manufactured products are built within a tolerance range. That is, some will read higher, some will read lower. The majority will read around about the average. With that range in mind, the manufacturers have to be aware of the legal requirement that no speedo will ever show a slower speed than the actual speed of the vehicle. Ever.
So the manufacturer has to aim to produce speedos so that (for example) the ones that are 'the norm' will read (say) 65mph when the true speed is 60mph. In that way, the ones that come off the production line that read lower than the average will still never read above 60mph when the true speed is 60mph.
In fact, the manufacturers have quite a big tolerance range for the speed indicated on their speedos. In the UK and europe, this must never be lower than the actual speed, and must never exceed 10% +6.25mph. So for a true speed of 60mph, the readout could be anything from 60 to 72.25mph. Statistically, the majority will be a little either side of 66.125mph, with a small number approaching the extremes. Yours might be one of the ones that came off the production line at the extreme end of the tolerance limit.
When the testing is done, they speedos are tested at the extreme end - so brand new tyres are used with deeper than normal tread, over-inflated, higher temperatures - all to make sure that there are no circumstances when the speedo can read lower than the actual speed.
But if the speedo does indicate a true speed (eg with speedo healer), it is a temporary thing. The speedo readout is very much dictated by the tyres, the temperature, the amount of air in there, how worn they are ...... At 100mph a worn tyre will read about 2mph different from when the tyre was brand new. (it has lost 2% of its diameter in tread wear).
Similarly, your satnav readout isn't necessarily accurate. It doesn't show your current speed, it calculates the speed you have been travelling over the last few satellite fixes, and it will be a few seconds behind - assuming that you are not surrounded by trees, buildings, mountains etc, when the positional fix may be wrong.
Also, note that if the satellite fix is lost, then some modern satnavs seem to assume that you are maintaining the same speed as you were before it lost the signal - without any warning. Try it. Note your speed as you enter a tunnel. Then speed up and slow down. Satnav stays fixed at the same speed - mine does anyway. The funniest readout is when you emerge into daylight and the satnav has to catch up with where you actually are. For a second, I've seen it read out over 100mph when it calculates my speed based on its assumed position and my actual position. I was only doing 30, honestly officer.
So, I do my own speedo healing. I wait until I am an open road, the tyres are warmed up, I am able to maintain a constant speed, and the satnav speed readout is staying put. I then note what my speedo is saying compared to the satnav. If it says 64, and the satnav says 60 then I can be fairly sure that for the rest of the ride that 64 on the speedo is an actual 60 - unless the temperature has a significant change.
Sorry - that was a long answer to a simple question. I'm off to see what I can find out about that VFR1200 now.