I am going to be in the market soon for a new ZX10R and I wanted to know what the difference is with the 49 state legal bikes and the california bikes. It might make a good excuse for me to drive home to Washington..
Most new bikes have very little to no performance differences between 49 state models and californicated ones. It used to be the evaporative emissions systems were the biggest thing, adding weight to the bike. Some models had california spec cams. I think those days are over though.
One other thing to be aware of, if you purchase a motorcycle out of state you will not be able to register it in california. You'll have to find someone out of state to register it to, then when the bike has 7500 miles on it you can then bring it legally into the state and put tags on it... oh, and pay your tax :rolleyes .