Tyre Sealant for Tubeless Tyres

Depending on their composition, tubeless sealants mostly differ in terms of:

• Sealing performance
• Durability
• Temperature resistance

Some manufacturers add more fillers to seal larger holes or cuts. Accordingly, the sealant may tend to form lumps or dry out more quickly. The temperature range is usually indicated on the packaging, but this only becomes important in winter when temperatures are well below freezing. Many manufacturers also rely on environmentally friendly formulas and do not add ammonia, for example.

You can fill your tubeless tyre with sealant in different ways:

1. When fitting a tyre, you can fill it directly into the tyre, before levering the last piece onto the rim.
2. With a syringe into the valve, after having removed the valve core from it.

The first method is particularly suitable for the initial filling of the tyre. It is faster and you can also use a measuring cup instead of a syringe. However, you should have some practice fitting the tyre to avoid spilling. The second method is also suitable for refilling sealant. There is, however, a greater risk of a sticking valve due to inaccurate work.

The service life of the tubeless sealant depends on various factors, such as the frequency and intensity of use and the environment in which the bike is ridden. If you use your bike often and in different conditions, the sealant can dry out or clump more quickly. Most manufacturers therefore specify a shelf life of between two and six months. At the latest when holes are no longer sealed or the tyre loses air faster than usual, a change is due. In principle, however, you should not wait longer than 6 months to change the sealant to ensure optimum sealing capability.

The optimum amount of sealant depends on the size of the tubeless tyre. In most cases, 50-100 ml of sealant is sufficient for one tyre. The following figures refer to 28 inch or 29 inch tyres and can be used as a rough guide for most manufacturers:

• Approx. 50-60 ml for road bike tyres
• Approx. 70-80 ml for gravel bike tyres
• Approx. 80-100 ml for mountain bike tyres

Some manufacturers also deviate significantly from these values. You will usually find precise instructions on the packaging. Also note that in addition to the tyre width, the wheel size also plays a role, especially with mountain bike tyres.