Aufitt got it - it's the gearing.
The CBR doesn't have enough power to pull the stock top gear to reline - no matter what you do or weight or...
You need to gear-down, as Aufitt said, to get your top gear RPMs higher and get the engine closer to peak power. If you do, your cruise RPMs will be higher as well, which could be a pain. Most cycles will not pull top gear to redline, usually because typical highway cruise gets too hectic.
As far as reving, there's usually no reason to hit the rev limiter - even if you are trying for max acceleration. I'll look for a dyno chart (EDIT -http://sites.google.com/site/tommysc...e/Untitled.jpg, from that dyno chart I'd shift at 10,000RPMs most of the time - slighly higher from 5th to 6th)
, but generally if you just slightly (500 RPM) exceed the RPM where max HP is made before shifting you will stay close to the power peak for the most time - giving you best acceleration. Don't be afraid to spin the CBR's engine - it's designed to live comfortably at higher RPMs. Use a quality oil (synthetic is always my choice) and change it often enough - more often than the manual suggests IMO.
Really, unless you change your gearing significantly or do a lot of mods the CBR isn't going to be much faster. You just have to deal with that or buy something bigger.