Tire/ tube sizing help..
 

I recently got a flat.. i patched it up just fine, however, I would like to buy a few spare tubes to have in case of emergency.

My tires have a few things written on it.

(28x 1 5/8 x 1 1/8) (28-622) 700 x 28c

I know my tire size is 700 x 28c

My tube says (25/32-622) 700 x 25/32c


Now, does the C mean circumference?
And what do the other numbers stand for? Width and height?

thanks

"c" is a letter designation for width of tire used in a now meaningless French sizing system.

622 is the bead seat diameter of the rim in mm

700 is the diameter of the wheel with the tire on, assuming you use just the right tire.

More tire sizing tidbits courtesy of Shelton.

ok.. so what is the tube size i need... every store online sells them differently.

Ah, while looking online, almost everywhere in the US and the UK will have them listed as 700c, then shoot for a 25-32 width.

You'll also want to get the appropriate valve length. How deep are your rims? Oh, and valve type as well. Probably presta, but they do make Schraeder 700c tubes also.

For what it's worth, we have 13 bikes in the family, tire sizes from 700x23 to 700x41 on the roadies and 26x1.4 to 26x2.3 on the mountain bikes. The only tube sizes I've bought in at least 10 years are 700x25 and 26x1.5. It simplifies inventory, and i've never had a problem. They're rubber; they stretch.

would the inner tubes 26 * 1.5 fit a 26 * 2.125?

do you think a 26*2.125 would fit a 26 * 1.5 slick

They WOULD fit; just not perfectly -- how important is that to you?

THEORETICALLY, the 1.5 tube in a 2.125 tire would stretch thin, making it easier to go flat; but since a 26x2.0 tube, inflated outside the tire, is as big as a hula hoop (4' across, tube 3-4" thick), I'm not too worried about that.

The only problems with the bigger tube in the smaller tire is a bigger chance of pinching the tube in the bead when mounting, and an ounce or two more rubber.

I always go small on tubes. For example, I just put, IIRC "23-28" tubes in my 32mm tire. They're much easier to install w/o bunching up and I really have no fear about undue stretching. First, I've never had the problem and second, when you think of it, anything that comes through the tire itself is going to puncture your tube whether it's full thickness or a little thinner.

I use the same rationale for buying lightweight tubes instead of regular for my go-fast bike. Actually a cheap way to save quite a bit of wheel weight with no consequences (again, in my years of experience).

I talked to my LBS and they pointed me to some 700 x 25 tubes.