Hard to tell, with this much information, mainly because Collegiate bikes were made for a long while.

Here is one way you can figure an equivalent width:

- I am pretty sure that the Caliente takes 27 inch tires
- I suspect that the Collegiate takes 26 inch tires
- the width of 26 inch and 27 inch tires is measured in inches (the 26 inch is decimal, the 27 fractional)
- look at the sidewall of the tires of the collegiate for the width. Should be something like e.g 26x1.35 (I suspect that it is not MTB-wide)
- turn that into the functional equivalent = 1 3/8 and try to look for 27 x 1 3/8 tires (pretty much the largest size 27 inch tires around 35 mm)

plenty of them online or at your LBS

good luck!