The speedometer healing device will cause your AN650 to run with higher RPM's for the same (true) speed, which also gives increased engine braking
This thread: viewtopic.php?f=26&t=53283&hilit=+bypass
describes how to route the unaltered speed signal to the ECU.
I have gone full mounty and purchased a second healing device, which will send an increased speed signal to the ECU, causing the bike to run with less rpm than standard - like eco or winter mode in a car.
I have already tried out the effect, but having the speedo showing 20% to much made 2 healing devices a necessity.