I've noticed the same thing already in the first couple weeks of having my RG. Cruising on the interstate at 75-77mph it appeared that more people were passing me than is typical when I do that speed in the car, so I started to wonder. Then the other night I was following my wife home. My speedo showed 65-67, she said she was doing 62-63 according to her car's speedo.

 

mine too.

 

I have a Garmin on my Ultra, and in Map mode (no-destination-set) it displays your speed. I find that on the highway you will find your actual speed, according to Garmin, is about 3-4 mph slower than speedometer. Faster you go, farther off it gets. Haven't had to sell that idea to a law enforcement officer yet, knock on wood!! Good luck!

 

mine is at about 3200 rpm in 4th at 55mph

 

I would get the dealership to fix it and document the faulty speedometer. Take the paperwork to the District Attornys Office before way before the court date. Yes it may cost you more than if you fixed it yourself but you have a dealership showing a faulty speedo. This should have the citation dismissed.
I alway use my GPS for speed as it is more accurate than the speedometer. My bike is always 3-5 mph off depending on my speed.

 

Mines off 3 mph, but on the good side. I always go by my Garmin. I agree with getting the Dealer to verify and get the ticket dismissed. Good Luck!!

 

Good luck trying to get Dealer to fix, you have to buy a tuner to adjust the speed sensor.