Just over 1,000 miles on my 2014 and am curious if anyone has had the opportunity to check these bike's speedometers against a GPS or radar gun. I have NO reason to think it is not pretty correct, but have had bikes (my '09 ST1300 for one) that overstate the speed by about 10%. The Interceptor just runs sooooo very nicely and 75MPH feels like 65, hence the question.
I found that most of the magazine reviews that included this generally showed a difference of 1 mph at 60 (speedo displayed 60 when actually going 59). But I haven't actually checked mine yet.
Passing a radar gun, the speedo was very close. Perhaps one MPH off as noted above. I was surprised, as the '98 I traded in was 8-9% off by GPS. Most of the Japanese bikes seem to be way off. The '13 F6B I have is also accurate. A nice change!
My speedo agrees with my Garmin VIRB gps camera within 1 mph at up to 100. I expect this to change a bit as the rear tire wears. But much more accurate than my 03 VFR which had a seven percent error (optimistic side) in that speed range.
Altitude 8300', 53 degrees F, no wind, no vehicles or people, flat straight roadway with hundreds of meters of clear space to the sides (no fences, cows or deer) and in the middle of nowhere. With that established, it took 28 seconds (verified with video using Garmin VIRB GPS camera) to run up from 60 to 143, within about 1000 rpm of redline in 5th, by which point body position had a significant impact on velocity (hug tank, pull toes in, etc). So yes in my estimation, maxed out with my 220 pound six foot fully geared up payload and 8/10ths fuel load.
I suppose there might be a combination of altitude and temperature and horse jockey physique that might add a bit more but that's what I had to work with.
It is perhaps noteworthy that I pulled a GPS confirmed 133 on the same roadway in similar conditions on the 03 in 2007. Indicated 142.
So, clearly the new Interceptor has a far more accurate speedo.