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I did a seat of the pants vib survey on the drive home today on my 650SS. With stock gearing it is glass smooth up to about 47 mph, then a bit of a resonance between 47 and 49 mph (2800 rpm), then smooths out to just a very minor level of vibration felt through the bars (not quite glass smooth as I previously posted) which remains constant through 70 mph (4100 rpm) up to 80 mph (4700 rpm), which is as fast as I thought I should briefly accelerate to while still in the break-in period. I could start to feel just a slight bit of vibration through the pegs at 70 mph and above. The mirrors are clear and for me, the vibration is really quite minimal for vertical twin. I feel could cruise all day at 65 mph, which is a about as fast as I want to go on an unfaired motorcycle for any length of time. The handlebar resonance point would probably change if I removed the lead shot that I added, but I am very satisfied with the current comfort level as is. While dealing with the previously installed heavy JP pistons, I did have both wheels balanced, verified equal timing for both cylinders, and made sure that the primary chain was adjusted correctly, so I am sure all that helped.

<blockquote data-quote="raleypc" data-source="post: 192904" data-attributes="member: 3060"><p>I did a seat of the pants vib survey on the drive home today on my 650SS.&nbsp; With stock gearing it is glass smooth up to about 47 mph, then a bit of a resonance between 47 and 49 mph (2800 rpm), then smooths out to just a very&nbsp; minor level of vibration felt through the bars (not quite glass smooth as I previously posted) which remains constant through 70 mph (4100 rpm) up to 80 mph (4700 rpm), which is as fast as I thought I should briefly accelerate to while still in the break-in period.&nbsp; I could start to feel just a slight bit of vibration through the pegs at 70 mph and above.&nbsp; The mirrors are clear and for me, the vibration is really quite minimal for vertical twin.&nbsp; I feel could cruise all day at 65 mph, which is a about as fast as I want to go on an unfaired motorcycle for any length of time.&nbsp; The handlebar resonance point would probably change if I removed the lead shot that I added, but I am very satisfied with the current comfort level as is.&nbsp; While dealing with the previously installed heavy JP pistons, I did have both wheels balanced, verified equal timing for both cylinders, and made sure that the primary chain was adjusted correctly, so I am sure all that helped.</p></blockquote><p></p>

[QUOTE="raleypc, post: 192904, member: 3060"] I did a seat of the pants vib survey on the drive home today on my 650SS. With stock gearing it is glass smooth up to about 47 mph, then a bit of a resonance between 47 and 49 mph (2800 rpm), then smooths out to just a very minor level of vibration felt through the bars (not quite glass smooth as I previously posted) which remains constant through 70 mph (4100 rpm) up to 80 mph (4700 rpm), which is as fast as I thought I should briefly accelerate to while still in the break-in period. I could start to feel just a slight bit of vibration through the pegs at 70 mph and above. The mirrors are clear and for me, the vibration is really quite minimal for vertical twin. I feel could cruise all day at 65 mph, which is a about as fast as I want to go on an unfaired motorcycle for any length of time. The handlebar resonance point would probably change if I removed the lead shot that I added, but I am very satisfied with the current comfort level as is. While dealing with the previously installed heavy JP pistons, I did have both wheels balanced, verified equal timing for both cylinders, and made sure that the primary chain was adjusted correctly, so I am sure all that helped. [/QUOTE]

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