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So I need to replace my inner tube as it got destroyed beyond any repair I can make (a hole right under the valve) but unfortunately I dont know what size the inner tube should be and I cannot figure out the different types of measurements of tubes. The metal part of the wheel has the markings 700x22 A/C, while the inner tube is too worn out to make out anything on it (Ive had it for like 2 years and I patched it 3 times :D )

The wheel is on the front and its a mountain bike, If that matters.

marked as duplicate by mattnz, andy256, Criggie, Batman, RoboKaren Mar 6 '17 at 19:48

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Look at the tire. it will have a size on the sidewall. Something like 29" x something or 26" x something or 700/700c x something. Tubes are sold with a range of sizes like 700c x 20 mm - 25 mm. You just need to be within the range (or close to it).

Alternatively, you'll find a number like ISO/ETRTO 20-622. The 622 is the wheel size in ETRTO standard (in this case, 700c for common people), and 20 is the tire size. So the above 700 x 20-25 mm would work here.

I'd guess that you're running a 29er with a 22 mm rim width, so you'll need a 29" x something tube.

Also, check the valve -- the common ones are presta (little screw you have to undo to pump) and schrader (like a car). You'll want to match this with the rim (use whatever is in the rim already).

  • A number I found on the outer tire was 700x36c, would that be it? – Arszenik Mar 1 '17 at 23:18
  • Consider adding info on the choice of valves too. Presta is uncommon on MTBs but not impossible. – Criggie Mar 1 '17 at 23:24
  • @Arszenik - Yes. so you need a 700 x a -b tube where a is less than or equal to 36 and b is greater than or equal to 36. And as criggie points out, the right kind of valve. Presta is not uncommon on MTB's (at least state side). – Batman Mar 2 '17 at 2:03

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