please look around the web for an installation manual (lots of site have one & all are pretty much the same)
you do need to cut the inner rubber as shown in manual, also rule-of-thumb is to dish sprocket in for skinny tires (mtn bike) and dish it out for fatter tires (cruisers)
Thanks. I was kind of having fun assembling without instructions but now I know how to get them.
When I was a kid someone gave me a bunch of odd parts and when I figured out how to put it together it was kind of like the Razor skateboard things they make now but it had a platform that you rock back and forth to propel it. I'm still inclined to dive in without instruction on things but it's gotten me in trouble more than once!