A few thoughts ...
noted, the manufacturers are allowed reading that are too high. You can read about this in a decent Wikipedia article: https://en.wikipedia.org/wiki/Speedometer
. The relevant sections are Error and International Agreements.
The upper limit according to the European Union specs, for our Burgers, seems to be "... 110 percent plus 8 km/h for two- or three-wheeled vehicles that have a maximum speed above 50 km/h ...".
I can see where this has more relevance to chain-driven bikes, where you can easily change the engine/rear-wheel RPM ratios, by changing the front or rear sprockets. Or to bikes where it's easier and more probable to change the rear wheel size that's being used.
In those cases, I can see where the manufacturers have a vested legal interest in making sure that you're not speeding without knowing it. Of course, if you're messing with gear ratios and suchlike, then you're not riding a stock bike, so maybe they're no longer responsible. Maybe it comes down to changes a manufacturer can reasonably forsee that a customer might make.
Now, in our particular case, where you can't screw around with gear ratios and the tires are all pretty close in size, I think Suzuki is just taking advantage of the regulations.
That is, I think Suzuki is near the upper limit of allowable readings just to make owners, or test riders, think they're going faster. Put another way, I think this is a subtle marketing ploy ... kind of like ads, where we know that what's being said is mostly BS, but the advertisers are trying to wring out whatever they can in our subconsciousness. Yamaha got sued some years back, for over-reading the upper RPM limit on one sportbike -- just a bragging-rights kind of thing among some riders.
I decided to go through the last half year of Motorcycle Consumer News issues (not a difficult task, because I have the PDF downloads from them) to see what other folks are doing lately.
MCN, when the do a full review of a bike, lists the actual speed when the indicated speed is 65 MPH. (I recall from reading MCN over the years that use a radar gun, but I can't be positive that this is still the case.)
In any event, here are the last half year's worth of bikes, and the actual speed when the indicated speed was 65 [EDIT: I had this backassward in my initial post]:
2017 Triumph Bobber: 63
2017 Moto Guzzi V9 Bobber: 64
2017 KTM 1290 SUPER DUKE GT: 64
2017 HARLEY-DAVIDSON CV0 PRO STREET BREAKOUT: 63
2017 KAWASAKI Z650: 62
2017 MOTO GUZZI MGX21: 63
2017 BMW R NINE T SCRAMBLER: 64
2016 MOTO GUZZI V7 II STORNELLO: 63
2016 HONDA AFRICA TWIN: 64
2017 harley-Davidson Road King (FLHR): 64
2017 Benelli TNT600 Tornado: 58
Only that last one, the Benelli, seems to be in our neighborhood of 9 or 10 percent. So, yeah, Suzuki could take less advantage of the allowable fudge factors, and it would be more in line with other manufacturers (or so it seems to me).