My '96 FXD came with a V&H Propipe on it. The PO also included the pile of parts that was the stock system. The Propipe liked to rattle its baffle screws loose and it had a broken heat shield mount.
Last night I put the stock system on and took it for a ride. The vibration that was at 55 to 65 is mostly gone as is the Cadillac smooth ride from 65 up. 70 mph is very buzzy now.
I'm surprised at how much the pipes affect things .

 

Funny how stuff works. I went to a 2-1 cause I liked the look and sound. Got an added benefit in that the vibes above 75 went down. A good bit too.
Not sure why , just enjoying the bike a little more.

WP

 

I would throw some loctite on the baffle screw put the propipe back on, or go get it tuned if your going back to a restricted stock pipe tuning will be much different