With all the posting I have read and as well as the other post I have read my eyeballs are floating...Still a bit overwhelming for me but I'm starting to see the whole picture...
I feel that the 58mm will be the largest I should consider on the 120R build I'm considering however will probably go with the 50mm bored out by Zippers to a 54mm and have them install the 58mm body on the tail end to hopefully get the best of both worlds which is what they recommended...
I'm not sure there are many dyno tuners in this area that will take the extra time to tune it properly with a larger T/B on it which from what I gather will be needed to keep the manners in low manuvering riding pleasing as well as the temperment down to where it should be for driving reliability...
I want To thank all of you for your insight and sharing your knowledge hoping to shine a bit more light on this subject to help educate us...

paul