The gearing is 48/39/28 T 12-25 cassette only problem I could only ride it around in the parking lot. So I couldnt go on a straight -a -way
(to me that doesnt seem big enough to get me the fast speed I want. Since Im used to 53/40t 14-26. I'm afraid I will just spin my grears adn wont go anywhere.)
48/12 = 56/14
56 is greater than 53.....
thus it has taller gears than your current ride
Just ride your current bike 24 miles per day, everyday for a few months, then you should be able to keep up.....