Rear wheels width

[cueball]

I am looking at getting a set of RC Components wheels for my '04 Busa the only question I have is, I believe the factory wheel is 17x6 and the wheels Im looking at are 17x5.5. Will I need a spacer or is that .5" not going to make a differance? Please help....

 

[sixpack577]

The 5.5" and 6" is the the width of the rim, lip to lip on each side. That number does not refer to the hub size, which is going to have to be made to fit a gen 1 or 2 Busa.
If they are available for Busa's in both widths it will have an effect on which width of tire you can use and how they fit.