mrblue

I'm not sure. I will give you a step-by-step breakdown of how I get the tires on. I'm sure most of it will sound elementary but maybe there's a small step you're omitting. Bear in mind I'm using a 28c tire. If you are using anything smaller this may be what's giving you issues.

1. Mount one side of the tire on the rim.
2. Inflate the tube just enough so that it has some shape.
3. Insert the valve stem into the rim and make sure the tube is seated in the rim all the way around.
4. Push up on the valve stem (toward the outer edge of the rim) just a little--enough to seat the bead.
5. Move around the rim seating the bead by gently rolling it over the rim edge.
6. When you get to the point where it starts to get hard (last few inches) release the air from the tube.
7. Go back to the point of the tire where you started and firmly press the tire, on both sides simultaneously, toward the part that is not yet seated on the rim.
   1. This will give you whatever precious few fractions of millimeters you may need to get the final portion of tire over the rim.
8. Starting with one side of the unmounted bead, while the holding the other in place, firmly roll it over the rim edge.
   1. It may not feel like your moving it very much, but you are. Little bit at a time.
9. Switch sides
10. Repeat until bead is seated.

This is how I do it and it and tire goes on super easy every time without tire levers.