I wonder if this lateral movement is what I'm feeling. I haven't had the chance to really ride my fat bob much yet, but a few times when I was on a good, mildly aggressive line with it, I felt something happen with the back tire. It felt like the rear tire was suddenly on its own line, wider than mine. I didn't feel it hop or skid or anything, it just sorta feels like it slips into a wider line on its own.

Then again my tires are getting down there in tread, about 3/4 of the way to a change so it could be that as well. Doesn't feel like it though. Feels like the floor coming out from under you.

 

I have often wondered why my rear fender vibrates back and forth when idling. This is why. Seems engine alignment and rear tire alignment are not independent.

 

.......

 

Yes and no. The rear tire alignment can vary quite significantly due to spacer setup, axle adjuster (HUGE factor that's often glossed over. You can easily get +/- 5 degrees or more here.), and swingarm pivot slop...not to mention swingarm geometry itself (bent, warped, poorly jigged during welding, etc)

 

You pay an independent motorcycle mechanic to work on your Dyna that didn't know a Dyna swing arm pivot shaft runs thru the transmission case and not the frame? Find another mechanic.

 

His specialty is sport bikes. No one wants to work on Harleys.

 

 

I do. But only my own.

 

 

Yep, hard to find an indy that knows how to work on Harley's.... which is weird, because I think my Dyna is one of the easiest bikes I've ever worked on.

That said, I do all my own work.