Gas milage C50 vs C90

I have a 2005 C50 with 21 inch Memphis Shade windshield. I can get 50 mpg if I hold steady throttle at 70 mph on highway. I am thinking of upgrading to a C90T. What kind of fuel milage can I expect from a C90T. I will be ridding from Alabama to Arizona and back. 

I have a C90T,,2005 stock ,,,, I get 45,,,50 miles to the gallon...
 

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ORIGINAL: astbombtech

I have a 2005 C50 with 21 inch Memphis Shade windshield. I can get 50 mpg if I hold steady throttle at 70 mph on highway. I am thinking of upgrading to a C90T. What kind of fuel milage can I expect from a C90T. I will be ridding from Alabama to Arizona and back. 

My bike is new.  Have not had first service yet.  How long before you start to see this kind of milage?