Bicycle Mechanics - Tire somewhat loose on the rim. Too small?

700x28 tire on a 622x19 rim should work, right? I was lead to understand this is the smallest tire that could possibly work on a 19mm rim.

Maybe not, though.

It feels relatively loose in that and I can easily roll the tire off the rim with my hands (no tube or deflated tube.

Tire width
Rim width
(interior) 18 20 23 25 28 32 35 37 40 44 47 50 54 57
13 X X X X
15 X X X X
17 X X X X X
19 X X X X X X
21 X X X X X X
23 X X X X
25 X X X X X

What happens when you have inflated to the manufactures specs? it should stay on then. Be happy it is easy to put on, and take off, may are not so easy.

What brand is the tire?

Bontrager R1.

Matrix 750 rim.

First inflation the tube blew out. . somewhere.

Are you sure you have a 700C tire, not a 27" tire?

A 700 x 28C tire on a 19mm inside width rim would fit somewhat loosely, and it would be quite easy to trap the tube under the tire's bead during installation. This would cause the tube to push the tire off the rim and blow out. (Been there, done that.) If the tire is indeed a 700 x 28C, I'd be careful with installation and inflation, making sure the tire is seated properly on the rim at first and re-checking every 10 to 15 psi while inflating.

Are you sure you have a 700C tire, not a 27" tire?

These are only available as 700x 23c,25c,28c&32c, no 27"

I guess I'll have to do the poco a poco inflation.

The other mount with a tube with a slight bit of pressure, the tire eems seated ok. Another thing about this tire is the beads don't seem very robust. Like there's not a whole lot for the rim to hold on too. Sigh.

Think this might be a case where manufacturers fudge tire size to keep the weight down? Seems SILLY at this price point. These were the only 700x28 in the shop too.

Meh.

Your rim is fairly wide and probably has a nice deep well in the center. This will make mounting and removing any tire much easier. But if you inflate the tire it'll get pushed out to the edge of the rim where the inner diameter is to spec and seat.

The only issue is that since you have room for it to shift, you need to inflate to about 20psi, then check all the way around that ot's properly and evenly seated before going to full pressure.

BTW- my commuter rims are the same way. It's a real joy to change a flat without any fuss or needing tire levers. Just push to center and pull the tire off, mount the same way in 5 seconds.

Your rim is fairly wide and probably has a nice deep well in the center. Yep. Exactly. Good call.