Head Shake
Hey Pete, Do you do wheelies on your Roadster? If you do, you may want to check
your front wheel bearings. Imagine the force on them when that monster touches the
front end back down! Extreme impact load. Second, METZLERS ARE ABSOLUTE **** on this bike. When I got my R3T, it had them. I was leaving my house one day and went to check my pocket for my cell phone and when I took my left hand off the bar, the bike began to tank slap on me! At about 35-40 MPH. That's with a new tire. They are JUNK!
Also check for a shiny rectangular spot on your wheel. If you find one, you've "thrown" a wheel weight. I can also suggest the Dunlop D251. They work really well on this bike.
Good luck, stay safe.