What`s the manual say , i think they do have like a dimmer ?

The instruments don't have a dimmer.
Lots of guys in the states buy superbrights (LED) for the gauges in any color but the speedo and tachometer will need to go to a instrument shop to be opened and the globes replaced with a brighter or color led.

http://www.hdforums.com/forum/touring-models/541489-led-gauge-lights.html

http://www.superbrightleds.com/cgi-bin/store/index.cgi?action=DispPage&Page2Disp=%2Finstrument.html

 The other way you can go is to buy a set a set of digital gauges & replace them yours thats what I did 

Do the ultras have a dimmer ?

Hey Baloff, did ya get ya dials fixed for illumination yet. or did ya take it back for warranty.