Cheers Indica!Yes you can ....
hey mate i have run 1.9 inch tubes in a 2.5 minion. seemed to work fine despite the obvious size difference.
You were probably didn't seat the tire bead properly.be careful though, dont get too smaller tubes, i had a 1.95 tube in a 2.5 inch hookworm and it blew up on me
Hahahahaha Danny I remember when that happened when I was at yours once. LolYep they should be okay.
Although if you do put a tube that is too small into a large tire, e.g. (1.25 tube into a 2.1 tire) it can "egg" the tube.
And yes I have had this happen to me before. It does work but when you take the tube out, there is a definite egg in it.