what the difference between tm42 or a tm45 mikuni carb looked at part#s the carbs are alike with the one difference cfm and the filter side of carb 213cfm vs 237cfm has anyone out there modded the 42 to a 45 or are my eyes and brain not all in tach?

 

I know the TM45 and 48 are about identical, haven't played with the 42mm yet. I would say that there is a difference to be felt though. Have to have the exhaust to let the volume in escape also.