I followed this video when I installed my SpeedoHealer V4 on my Vmax 1700 2009.
My speedometer show 8% off. I checked at 20,40,50,60,70,80,90 &100.
First I power up unit at home with 12,5v and programmed it to A-8,0
I installed it and when I go out for a test, I run about 35km/t (limit 30)...