Odd vibration to me.

[1966F100]

Doing searches:

Last week I took a ride from Texas to Michigan for family time.
Halfway there running Interstate my 2002 XII developed a vibration. When I would back out of the throttle, aka while slowing for semi's crossing my lane, it would start a 'deeper' lower freq vibration different that the straight cut gears vibes-noise.

When I would stop for a rest area or gas the vibration was gone till another 'Back off the throttle' slow down.

At first it could go away after a few miles but return with the throttle backing off in gear.

Now it comes on after riding it for over 20 minutes.

I thought maybe the u-joint but it seems more motor/trans location to me.

Something in the clutch system?

[cranky]

... first step.... clutch in / out, does it stop or keep going? Is the problem in the motor
or final drive/tires?

[cushman eagle]

1966F100,aside from what cranky suggested,it could be the u-joint.

[1966F100]

It does change some when clutch is disengaged. It concerned me enough to rent a Penske and haul it home on the off chance of something breaking on the way home.

It was more in the 2800-4,000rpm range. I did adjust the counter balance shafts.