'09 Dyna bounces vertically a lot at idle. Motor mounts are new. Replaced all sensors, but not the IAC. Cleaned the IAC, but no appreciable effect. Injectors are new. Replace the IAC?

 

If you mean there's visible engine vibration and movement at idle but it smoothes right out with a little bit of throttle, that's the normal behavior of rubber-mounted Twin Cams... Is it fine once you're riding?

 

All stock?

Condition and quality of tune (including idle speed!) as well as any aftermarket mods (including pipes!) can greatly affect idle quality.

 

Stock. Idles like a ditch pump. Didn't used to.

 

Honestly? All that doesn't mean crap if you got stuck with cheap/bad gas. (too much ethanol?)