Vibrations in handlebars

[Grayrider]

I took my first day trip yesterday and unfortunately I was a little disappointed with the vibrations that I felt in my new (to me) 99'RT's handle bars. I left my house in Louisville KY and headed out for US 129 in TN, better know as Deals Gap or The Tail of The Dragon on the TN NC line. 280 miles later I was eating lunch at the diner on the other side. After lunch I headed back for home going over the dragon one more time. 318 curves in 11 miles was just plain awesome! I covered approximately 580 miles in 11 hours. I averaged 44 mpg for the trip, not bad I thought.

 

My complaint. Once I got up to 85-90 mph I felt a considerable amount of vibration in the handle bars of my bike. It really surprised me as I was expecting a much smoother ride on my BMW. My front tire is a little cupped but I can't imagine that the cupping is responsible for all the vibration that I felt. My hands were a little numb on one of my gas stops. Are the vibrations that I felt normal for an RT or is something wrong.

[realshelby]

Probably only needs a good throttle synchronization! You won't believe the difference that makes in vibration in the bars and everywhere else.

[ShovelStrokeEd]

One factor might be that trip across the gap, both ways. That road can get you tightening your grip on the bars pretty easily.

 

Seriously, 580 miles, while not a really long day, with twisties included, can magnify what is a simple annoyance on a lesser trip. Especially so if you are not used to that long a day in the saddle.

 

All boxer style engines buzz a bit, most are at their worst around 4 to 4.5K RPM smoothing out as the revs move away from that range. My 1100S has a sweet spot right around 5-7K RPM but does buzz a bit if I let the revs fall into the lower 4000's. Simple matter for me, run at 5K or above, or 4K or below. That close ratio 6 speed gearbox makes it a breeze.

[BFish]

i agree with ed. just did 1300mi trip and while i may feel a "buzz" at times...don't think i've ever experienced a vibration. 5th gear at 70mph buzzes some, but no shake or uncomfy feel. closest i ever felt to a vibration was at low rpms in too high a gear. the bogging down feeling. what gears were you running? around there anything above 3rd may explain some of the issue.

[Beheme]

Probably only needs a good throttle synchronization! You won't believe the difference that makes in vibration in the bars and everywhere else.

 

Totally, 100%, right! A well-synchronized Boxer produces very little vibration at any (OK, almost any) speed. You may want to consider the Parnes adjusting ring that makes the job much easier.

http://www.marcparnes.com/BMW_Throttle_Adjusting_Ring.htm

 

Regards

 

Dominique

[T__]

Grayrider, at 85-90 mph you might be experiencing some front wheel balance problems.. A nominal wheel imbalance that is just a slight disturbance at 55-70mph could be a real bar shaker at 85+ mph..

 

Watch your engine RPM’s at 85-90 mph then slow down & drop back to 4th gear & run at the same RPM’s. If the bars shake as bad in 4th at the same engine RPM then you are looking at possibly engine related shake or even a normal engine buzz.. If the bar shake is only there at the 85-90mph but not at the same RPM in 4th gear look for a front wheel imbalance problem or some other first order tire radial harmonic problem (like uneven tire build or out-of-round condition)..

 

Twisty

[Grayrider]

Thanks for all the replies. This is why I come to this board!

[glockster]

Thanks for all the replies. This is why I come to this board!

 

You are not the only one!