X6 Street Glide not Ultra but smooth all the way up to 100.

 

I have over 6,600 miles on mine and it is smooth at any speed.

Have the dealer check it. Maybe the wheels weren't balanced correctly.

Your post begs one question. Why are you going fast on a new bike?

 

Because we can!! Its smooth on both of mine

 

Smooth at all speeds. 100+ two times was still smooth.

 

Balance your front tire. If it only vibrates at higher speeds it almost has to be that.

 

2600 miles and mine is as smooth as a baby's a$$

 

Whopping 500 mi on my RGS. Smoth as silk in all gears. Loving this bike.

 

I've owned many Harley's through out my life and the 2017 RGS is the smoothest one I have ever owned. Zero vibration till I get to 85 mph then the floor boards and hand grips start buzzing a little bit. I've had it passed 100 with no issues and only that little bit of buzzing.

 

no vibes, 90% of my riding between 70 and 95 mph. spent some time over 100 with no issue either

 

Mine starts around 2800 RPM up to redline. Shakes pretty good at idle up to about 1500 RPM too but I guess that's normal...?
In the olden days It would have me thinking shifted crank. Prob not that though.

Don't get me wrong, it's not bad, just noticeable.