The function of an inner tube is to ensure that the tyre/wheel assembly is sealed. To find out if you need an inner tube, start by determining whether your tyre is Tube Type (TT) or Tubeless (TL).
How do you know if your tyres are TL or TT?
- Tube Type tyres (TT)
These are tyres where the first layer of rubber on the inside is not airtight. They must therefore contain an inner tube to maintain pressure.
- Tubeless tyres (TL)
In tubeless tyres, the first layer of rubber is airtight. It is therefore not necessary to fit an inner tube to ensure the seal. However, there is an exception: if the rim is TT , an inner tube must be used.
Now examine your rims to determine whether they are TL or TT.
How do you know if your rims are TL or TT?
1/ Spoke rims
The spokes usually pierce the rim in the centre around the entire circumference. And since these holes imply a lack of sealing, this type of rim is Tube Type (TT). It therefore requires an inner tube.
However, there are rims with spokes that are fixed in other ways, in order to maintain the seal. This types of spoke rims are Tubeless (TL) and not Tube Type (TT).