man....the 30mm oko were a hot topic here awhile ago i know alot of guys were snatching them up basically they are keihin 28mm pwks bored to 30mm they interchange with all the pwk stuff so you buy the pwk floats jets.needles ect. I run the 28's on my bike in tight trails and i love them,, Just do some more searching for 30mm OKO's and see what ya find like i said alot of guys on here was running them at one time and loved them.....
Josh