I just finished a 3500k ride without any issues until I get home. As I accelerate through 2300rpm the bike feels like it's running over a rumble strip and then past 2500 rpm the vibration just disappears. Same thing happens when the rpm is going the other way. Any thoughts? I have 40,000 miles on it.

 

A bad motor mount?

 

.... or loose belt?

 

You could check the muffler hangers. If the mufflers can't move fore-aft with the motor movement it would be like a bad motor mount. I've had my mufflers slide rearward because the clamp wasn't holding. Eventually the right side muffler moved back far enough it was kind of jammed up on the rubber sliding hanger. It was odd because at some rpm/load combinations it was actually smoother than normal but other situations there was more vibration.

 

don't know if youy saw my response to your other post on this:

try to isolate whether this is an rpm issue

in which the vibration is related to the speed of the motor- regardless of the gear

OR if it is related to the road speed, regardless of the rpm

all gears, or just one gear

rolling clutch in/clutch out

left turns, right turns...stuff like that

if you can determine under which conditions the vibrations occur you can figure out if the motor is broke, or the rear tire is flat...or something less extreme


or maybe it means cdn riding season is done... ( just kidding-- it is not yet Labour Day yet)

mike

 

Would a tire being out of balance cause a vibration in the same speed/RPM range?

 

It seems to be strictly the engine. It only happens when the rpm's pass through the 2500 range. I just had the rear tire replaced the same day this all started. I have not had the chance to take the bike back yet but I am going to. I suspect the belt may be too tight or the tech did something to cause this.