GSXR 750 46 mm throttle bodies are the business
Pic I nicked from another site showing how easy it is to fit them if you use Suzuki rubbers and inlets as an adaptor for a DCOE manifod
A set I fitted to my turbo/MegaSquirt bike project
Another set I fitted to my RS2000
They are really good value for money and flow plenty of air, I've never given any more than £80 for a set of four and got some money back selling the bike injectors on ebay
Mark