imetazoa

I have been in contact with Niagra Cycle works whom I just ordered the Panaracer Pasela 700x28 tires from and Michelin Airstop A2 (labeled as 700x23-32) tubes from. I have been communicating with them because it appears that the Michelin tubes are way to big in diameter for my 700c CR18 Sun rims... (and too big to fit inside the Panaracer tire). The tubes themselves are labeled "Airstop A2 25/32 x 622/635." They say they havent had any complaints about the tubes before...suggesting that its probably not a manufacturing problem.

Is there something I am missing here???

Bianchigirll 

it looks to me that the tube is labeled to fit a 700x25 to x32 or a 27" I assume you are pumping air into the tube before installing it in the tire? the tube can get real big real fast and you just have to fudge it a bit, just put enough air to give it shape.

imetazoa

Yeah, I put just enough air to give it shape, but no where near enough to stretch it out...

By the way they "fit" my 700 rims they definitely look more like they are for 27" rims...

JiveTurkey

The circumference of 700c and 27" (1953mm and 1978mm, respectively) are so close (~1" difference) that tubes are generally made to accommodate both sizes.

25mm to 32mm is a huge range for the compatible widths, wider than I've ever seen. It's likely thicker than you're used to for a 700x25c tire, so maybe that helps explain why it's hard to shove it into the tire.

fuzz2050

My suggestion for this, don't even bother with the pump, just blow into the tube a little. It works great, it doesn't stretch out the tubes, and people give you really funny looks.

dscheidt

635 isn't 27" tires (those are 630). 635 is 28" size, used on old british roadster bikes. No wonder the tube seems too big for the tire. Get a tube locally.

cnnrmccloskey

it says 622/635, I assume thats a range

cny-bikeman

My guess is that tube is made to simplify stocking in places where there is not a lot of business and not a lot of choice - which exists a lot of places in Europe and elsewhere. One can make almost anything work if there is no other choice. I can't see how one tube can possibly work well for all those sizes. Return the tubes and get something that fits a narrower range, with your size at the top end of it.

achoo

I've got one of those tubes in a Michelin City 700x28 tire right now on my commuter bike. It works.

rccardr 

Weird. I have noticed this exact same thing recently. I've built a half dozen bikes or so recently, and have had three different brands of tubes that all felt too large in diameter for the tires. In each case, I had to be very careful placing the tube because it was so long it would flap and fold over, even with just a little air inside.

I thought it was just me, but maybe it's a direction being taken by the tube manufacturers, so they have to stock fewer sizes?

carbon4me

tube is wrong size for your 700c rim -- ds is correct

DannoXYZ 

What's your installation procedure? I find barely inflating the tube (with your mouth if you want to make sure not to overinflate it), then stuffing that into the bare tyre ensures you don't have any weird kinks or folds that can lead to flats later. Then install that entire assembly over one bead of the rim. Push sideways so tube falls over rim, then install the 2nd bead.

wrk101

+1 Its an installation technique issue.

10 Wheels

I am using 700 x 28-35 tubes in 700 x 28 tires.

No Problems.

scattered73

I run 700x25 thru 700x38 on my cross bike and use the 28-32 tubes for everything it's a little trickier on the 25 to install but it works.

Dilberto

The tube is the right size. A high-pressure 700c tube is actually supposed to almost "lift" off the rim, when fully inflated...hence the appearance of being slightly larger. As others mentioned - finesse the last part of the tube install with a tiny bit of air, when stuffing it inside the carcass.

Remember, its better to "crumple" the tube than fold it inside the tire - which almost always results in a pinch/fold flat.

Bill Kapaun

You might also want to pump it up to 10 psi or so and then remove the valve core to release the pressure to give the tube a chance to "equalize". I'll do that twice if my tube is on the "large" side of the tire size range.

Jeff Wills

Oh, no... a zombie thread!!

Homebrew01

I hope the OP has resolved it in the last 3 years

imetazoa

LOL! Yes, I have!!!

neurocop

Right. The apparent sloppy fit is due to the wide range of those "one size fits all" tubes. I've used them and they will work, but you've got to install them with care to avoid pinching. It's generally better to use tubes that are sized more precisely to your rim & tire dimensions,if you can find them.

Jeff Wills

Sigh...