Originally Posted by
huerro
.........can I use the shifters and rear derailleur in friction mode? And, if so, can I use one of the nice and cheap 11-28 mountain cassettes or will I have to pony up for a 12-25 road cassette?...........
It should work, the only question is whether the derailleur has enough range of movement to shift over the wider cogset. Usually, it's not a problem. Assuming that's the case, it should work fine with either the 11 x 28 or 12 x 25.