I recently popped the tube in my front tire and need help replacing it. I don't really know very much about bikes or the assortment of numbers on tubes, tires, and wheels. Here is what I do know:

The tire that popped has 700x35/43C on it.Old Tire

The spare that I got when I bought the bike has A2 25/32 x 622/635 on it. SpareTire

I was told that the spare is not the right size for my bike. I inflated it just a bit to see what it looked like in my tire and it does seem a bit small as it looks like it has a bit of room. Spare in 1 Spare in 2.

I just got a spare tube that has a schrader valve and learned that those cannot fit through the hole in my wheel. I'm not sure but I think this is the type of tube I need to get http://www.amazon.com/Avenir-Bicycle-Presta-25-35c-27-Inch/dp/B002K2DQ4S/ref=sr_1_10?s=cycling&ie=UTF8&qid=1337452869&sr=1-10 700 x 35-45c or 700 x 25-35c as I was told I need 35 to be in the range of the second set of numbers. Is this correct? Can I get these with a presta valve in a store (like Target, Walmart, etc local large merchant) or should I just order and wait?

For additional info: My actual wheel says it is 622x17 6061H-T6. On the inside of the wheel groove it looks like it is stamped 900x16. It looks like the tire name and brand is Alexrims G6000. It is a hybrid bike.

  • Frankly, that tube's just a hair undersize but I'll bet it will work, if your tire isn't too wide. We need to know the numbers on the side of your tire. May 20, 2012 at 1:01
  • The tire is for a hybrid bike and has a bunch of numbers on it. It has 37 x 622 in one part and 28x13/8x15/8 in another. It also says max inflation 70psi.
    – Aaron
    May 20, 2012 at 15:12
  • 2
    622 is the same as 700c which is (sometimes) the same as 28 or 29". The 37 is the width, which is about 1-7/16". You want a tube for 622 or 700c with a width range encompassing 37mm. Your new tube only goes up to 32, but will sorta work (temporarily) at 37mm, thought there will likely be a bump near the valve. May 20, 2012 at 16:54

3 Answers 3


Any bike store, and probably any Walmart/Target/etc, will have what you need.

700C (or 650c, 26", 29", etc) is how big around the tube/wheel is, while the x23,28 or x30-42, etc are the width range. You want to find one that, as you mentioned, includes the target size within the range and is a match on size and valve type.

Based on the "replacement" not fitting, I'm thinking your wheel is a 700c/29" and you are most likely looking for the right tube: 700x[range including 35] with a presta valve. That said, if you have a local bike shop, swing in there and the bike mechanic can make sure you are getting what you need. In most cases, the tube is going to cost the same (it's actually cheaper at the LBS I hang at as they buy tubes in bulk and sell them at close to cost) and you will be sure to get the right item.

Bonus: Ask the mechanic if he'd mind coaching you through changing out the tire. Someone who has changed a couple hundred tubes can usually give you pointers on how to roll the tire back on without tools, hot to prevent a pinch flat, and how to make the whole process quicker and easier.

  • Are 700x and 29'' interchangeable? When I was looking, I found a number of boxes that said twenty-something inches but ignored them for the smaller selection of 700x boxes. Is the 35 the width of my tire or wheel (inner or outer groove)?
    – Aaron
    May 19, 2012 at 21:24
  • 27" and 700c tubes are interchangeable. May 20, 2012 at 0:59
  • 1
    Not sure about the 27" versus 700c tubes, but the 29" and 700c should work interchangeably as long as right stem and reasonably close width. Road tubes are usually thinner and generally marked 700c, Mountain bike are usually thicker and generally marked 29".
    – Ken Hiatt
    May 20, 2012 at 3:42
  • 1
    Aaron: think usage first. If you take it off road, go with thicker tubes that can take more punishment (mountain bike). If you stay on paved paths and roads, the lighter road tubes. I would default to the worst general conditions that you take the bike across. Most hybrids are not super-light, so the slight difference in weight probably won't matter so if in doubt, go with the thicker.
    – Ken Hiatt
    May 20, 2012 at 23:43
  • 1
    @gaoithe - Most bike tubes are made of soft, flexible rubber, and they will stretch quite a bit. Most manufacturers label their tubes for both 700c and 27" use. Sep 2, 2016 at 11:40

You can stick just about any tube into any tire. Some of the weight freaks will buy a 24" for a 26" wheel, I even had a friend use a mo-ped tube in a BMX tire, just shoved it all in there. It works, but the problems you will have are not worth using them for anything more than a temporary "emergency" fix until you can find the proper size.

Using a tube too big will cause pinching and could result in a snakebite like flat. Using one too small will stretch it thin in places and might result in herniation which could lead to a blow out (very bad if you are going fast).

Walmart is convenient and cheep but sometimes they use inferior suppliers and I have bought a few tubes that have separated at the seams. I prefer to pay the extra $2 and go to an actual bike shop and get the better tubes, the pain saved in doing it right the first time is worth it.

When you are looking for the numbers you will want to make sure that you are getting "700 x 35-45c". Some tubes can be used on more than one size of tire, just be sure that number is somewhere on the box, and also why going to a real bike shop is useful, they can make sure you get the proper size. Also, as you can see in the first picture, most tubes will have the size printed on it, usually in white, the numbers in that second picture are not usually what you are looking for.


I don't know if department stores like Walmart carry Presta tubes. You had a Presta and need to replace it with a Presta. The size you need is 700x35 or 27x1 3/8. I like thorn resistant tubes. They are heavier and more expensive but will usually go 10 times further without a flat.

  • 1
    ...with the downside of increased rolling weight. On a MTB that rarely matters.
    – Criggie
    Feb 7, 2016 at 9:31
  • It depends on the rim whether or not you NEED a Presta. Maybe someone put a presta in a Schrader rim, I have done it a few times. But, if that rim is a preasta rim and hasn't been drilled out, then you are right, they will need a presta.
    – BillyNair
    Sep 2, 2016 at 14:57

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