Did you ask what size tires these were modded to fit? Keep in mind that you should be going by the ISO & not the fractional size.
http://www.sheldonbrown.com/tire-sizing.html
Fractional sizes:
Fractional ISO Applications
36 inch 787 mm Unicycles, some novelty bicycles
32 inch 686 mm Unicycles, some novelty bicycles
29 inch 622 mm This is a marketing term for wide 622 mm ("700C") tires.
28 x 1 1/2 635 mm English, Dutch, Chinese, Indian Rod-brake
roadsters
(Also marked F10, F25, 700 B)
622 mm (F.13) Rare Canadian designation
28 x 1 5/8 x
1 1/4 Northern European designation for the 622 mm (700 C) size
27 x anything except "27 five" and 609 mm Dutch 630 mm Older
road bikes.