I know finding your bike tube size can be somewhat confusing for the beginners. Fret not, I’ll make it super easy with images and charts. First step, you need to know the dimensions of two things – the diameter or size of the wheel and the width of the tire. Both can be found on the sidewall of your bicycle tire.
Example – 27.5 x 2.30: the first figure here refers to the diameter or size of the bicycle wheel, while the second figure is the width of the tire. Bike wheel comes in different sizes, such as 24″, 26″, 27.5″, and 29″. And the tire width can vary according to the bike type, ranging from 1.4″ to 3″. Look at the image below –
When selecting the right tube size, you need to consider the exact number/measurement of the wheel diameter. For the tire width, the exact number isn’t required as bike inner tubes stretch or expand. When you see a bicycle tube with this number – 26 x 1.75 – 2.4, the numbers 1.75 – 2.4 mean the tube will fit a tire width in the range of 1.75 to 2.4 inch. Got it?
Bike tube size chart
According to manufacturers, sizes on tires can be given in inches, mm, or ‘c’. A 700 x 28c tire (French system) has the same width as 700 x 28 mm tire (c = mm). Below is the inner tube size chart for different bike tires – for road, mountain, kids, gravel, hybrid, touring, and so on.
|WHEEL SIZE||COMMON TIRE WIDTH||TUBE FIT RANGE|
|12″||1.75″ – 2.125″||12″ x 1.75″ to 2.125″|
|16″||1.50″||16″ x 1.50″ to 1.95″|
|16″||1.75″||16″ x 1.75″ to 2.125″|
|20″ (BMX)||1.75″||20″ x 1.75″ to 2.3″|
|24″||2.2″ – 2.35″||24″ x 1.75″ to 2.3″|
|26″||1.85″ – 2.1″||26″ x 1.75″ to 2.4″|
|27.5″||2.3″ – 2.8″||27.5″ x 1.75″ to 3″|
|650b||2.3″ – 2.8″||650b x 1.75″ to 3″|
|28″/700c||1.4″||700 x 32mm to 47mm|
|29″/29er||2.2″ – 3″||29″ x 1.75″ to 3″|
|700c||20 – 25mm||700 x 20mm to 25mm|
|700c||25 – 28mm||700 x 20mm to 28mm|
|700c||32 – 45mm||700 x 28mm to 50mm|
ISO/ETRTO tire sizing
Most bike tires found in the US and UK are marked with either Imperial or Metric sizing. But, in some countries, you may also come across a tire size like – 28-622 (same as 700x28c), which is called an ISO / ETRTO sizing. Unlike the English sizing, the first number here (28) is the width of the tire in mm, the second one (622) is the diameter/size of the tire. Pretty odd, right?
Below is the ETRTO wheel size converted to English system:
|ISO/ETRTO TIRE SIZE||ENGLISH TIRE SIZE|
Inner tube valve types – choose the correct one
Now as you know the size of your bike tube, the next thing is to know the valve stem types of the inner tube. There are usually two common bicycle tube valves – Schrader and Presta. Let’s see the differences in the table below:
|Large, short, robust, and known as ‘car type valve’||Narrower, lighter, and smaller|
|Size – usually 8mm in diameter||Size – 6mm diameter|
|Found on MTBs, downhill, and kids bikes||Often found on road, aero, racing bikes as it requires thinner rims|
|Easier to inflate||Trickier to inflate|
|Suitable for bicycles that use low air pressure||Can withstand high air pressure|
|You can use a Presta valve on a rim compatible for Schrader valve||You cannot use a Schrader valve on a rim made for Presta valve as the hole is smaller|
People also ask
Are all bike inner tubes of the same size?
No. Bicycle inner tubes come in variety of sizes according to the wheel circumference and width of the tire. You need to select the tube size depending on your bike’s wheel sizes and tire width. Eg. 27.5 x 1.75″ to 2.1″, the first dimension (27.5) indicates the wheel size while the second figures (1.75″ to 2.1) indicate that the tube will fit tires within the range of 1.75″ to 2.1″.
What is the standard road bike tube size?
Most road bikes use 700c x 23mm/700c x 23c tires. So, we can say that the standard tube size of a road bike is 700 × 20 – 25mm. However, high-end performance road bicycles mostly use 700x28c inner tubes.
Can I use 1.75 tube in 1.95 tire?
Yes, normally a 1.75 tube should be compatible with a 1.95 tire. As long as the number is within the range of the width of the tire, the inner tube will easily fit in.
What size inner tube do I need for 700x38c?
For a 700x38c tire, you’ll need an inner tube labelled within this size range – 700×32-47mm. It’s even perfect if you find a tube with this exact number – 700 x 35-38”. A good rule of thumb is that the second numbers should be fairly close to your tire width.
If you are a cyclist, it’s certain that your bicycle tube will be punctured at some point of time. Also, keeping a spare inner tube at home is also a smart choice. The thing is, you cannot get it wrong while determining the correct tube. So, to know the right tube size of your bike, use our chart and guide given above. With the right tools, it isn’t difficult to replace the tube by yourself at home.