Motorcycle Repair: 6 spd revtech, speedo sensor, stock harley

Question
hi Mike . i just hd a 6 spd revtech installed on my 06 roadglide,while riding i noticed the speedo was reading about half the correct mph. the mechanic says we now need a calabration kit or something to that effect that plugs inline, then we need to mirror another vehicle at speed to set it. what do you think . i asked why revtech did not prompt us to this little tid bit my mechanic says the speedo sensor is now reading off the 6th gear instead of the 5th gear stock harley trans.
         signed confussed

Answer
revtech does prompt you in their info on the tranny. I would think the mech would know that the speedo is reading off a different gear.
Yes, you do have to calabration kit for the speedo. you dont have to mirror another vehicle. In the direction it will give you the way to do the calculation to set it.

Good luck and happy riding
Mike