Around 8% fast is typical. Do you have a first or second generation 1000, Vee or Veek according to my sig? There are plug and play solutions like the HealTech Speedohealer and the 12oclock labs SpeedoDRD that interrupt the signal and adjust it as needed. The Vee units are available as plug and play kits while the Veek needs a universal model that requires some cutting and splicing. The Veek doesn't have a dedicated speed sensor but interpolates speed from the ABS sensors and doesn't run the speed signal, power and earth wires through the same connector. Be aware if you install such a unit, the normally ~2% high odometer will read lower than actual mileage.