Why Carry A Spare Inner Tube?
Why Carry A Spare Inner Tube?
Why Carry A Spare Inner Tube? Nearly all bikes use an inner tube. If you get a puncture when you are out cycling the quickest way to fix it is to pull the old tube out and put a new one in. Trying to find the hole in the tube and patch it properly is not something you want to do at the side of the road on a cold and rainy day. You can always patch the old tube when you get home.
A spare tube will easily fit into a pocket or bag and should only take a couple of minutes to put it in. However, carrying a spare tube is only good if you have the right type of inner tube.
Which Inner Tube Do I Need?
There are loads of different sizes and types of inner tubes. To work out which ones you need there are two simple things you need to check. The first thing that you need to know is the size of your tyres. This will be written on the side of your tyre, however, it can sometimes be hidden amongst a lot of other numbers so it helps if you know a few general rules.
Inner Tube and Tyre Sizes
There are two different sizes you need to know for an inner tube. These are the diameter of the wheel and the width of the tyre.
Kids bikes – kids bikes tyres come in inch sizes. `The smallest will be 12”, they then go up in 2” increments until you reach 24” or 26” wheels. Most kids bike tyres will be fairly wide so expect to see numbers like 12 x 2.0. 12 is the diameter of the tyre, 2.0 is the width. The image below shows the size markings on the side of a 12x2.3 Specialized kids bike tyre.
Mountain Bikes – mountain bikes used to all be 26” but these days most will be 27.5” or 29”. Mountain bike tyres can then come in a massive range of widths from 2.0 to 2.8 or bigger. So you should expect to see numbers like 29 x 2.0. If you have a 27.5” tyre then a 650B tube will also fit. The image below shows the size markings from a 29x2.3 Maxxis mountain bike tyre.
Road bikes – road bikes use the metric system so the size of the tyre and tube will normally be 700. 23c used to be the standard width but most people now use 25c tyres so expect to see numbers like 700x25c. The image below shows the size markings for a 700x24c Specialized road tyre.
Hybrid bikes – hybrid bikes can use a whole range of different size wheels and a huge range of different width tyres so these are often the hardest to work out. Try to work out whether you have a 700 wheel like a road bike or a 26” wheel like a mountain bike and go from there. The image below shows the tyre size markings for a 700 x28c Trek hybrid bike.
VALVES
Your bike will either have Schraeder or Presta valves. If it has Presta valves then a Schraeder tube won’t fit the bike. Why there are two different types of valve isn’t really important here all you need to know is which one you have.
Shrader Valve
Presta Valve
Most inner tubes won’t be an exact size. So for instance they will come in 700 x 18-25c. This size tube would cover any 700 x 23c, 700 x 24c or 700 x 25c road bike tyres. Similarly, you might see a mountain bike tube that is 27.5 x 1.95-2.35. This would fit any 27.5” mountain bike tyre between 1.95” wide and 2.35” wide.
If you know the size of your tyre from the marking on the side, and you know the valve you need, you should be able to work out which tube to buy. If in doubt pop into your local Cycles UK store and we will work it out for you.
