John Rumm wrote:
Had a rather impressive failure of the rear tyre on my mountain bike
the other day - the rubber tore free of the bead, let the tube pop
out the side of the tyre and the break calliper shredded it nicely as
I was riding along. Loud bang and I squirmed to a halt - fortunately
on a quite bit of road!

Anyway, getting the tyres on an off these rims seems to be a *******
of a job. I know all the theory about how you are supposed to be able
to do most of the work with your thumbs etc. Now while that works on
most wheels, not these. Not sure if they are slightly over sized or
what, but the only way to get the tyre on or off seems to involve a
vice, lots of long levers and much swearing! I eventually got the
sodding thing back on the wheel on the fifth attempt - the first four
having to be undone to fix the holes I made in the tube getting it on!

Any suggestions for doing this the "easy" way?

As others have said, making sure that the bead has dropped right into the
lowest part of the rim on the diametrically opposite part of the wheel that
you're applying levers to is the key. A bit of trapped air in the tube can
make this difficult sometimes so do make sure that the tube is completely
deflated wheh removing the tyre.

Also, a little air in the tyre when fitting helps to prevent tube damage.

Always worth looking to see what the guru had to say on the subject.
(Sheldon Brown).

http://www.sheldonbrown.com/flats.html

Tim