TPU tubes are gaining attention as the third force in bicycle tires. We summarize its features, advantages and disadvantages of using it on road bikes and MTBs, and major manufacturers.
Table of contents
What causes a puncture in a tubeless or tubular lady tire?
On clincher (tubed) and tubular tires, the tire contains a tube, so some punctures are caused by the tube. Causes of tube punctures include tube wear and damage from rim strikes.
However, since tubeless and tubeless ready tires have no tube, the cause of a puncture is due to a “hole” in the tire itself.
In rare cases, the rim and tubeless tire may be incompatible, and an impact may cause the bead to detach from the rim and leak air, but this is not technically a puncture.
Therefore, the main puncture countermeasure for tubeless and tubeless ready tires is basically to “repair the punctured tire.
What if I get a flat tire with a tubeless or tubeless ready tire?
Refill the sealant.
Tire sealant is a special fluid that fills gaps and holes between the tire and rim. Without sealant, tubeless lady tires cannot hold air inside the tire.
Sealant was originally used as a “puncture repair agent” in tubular tires and MTB tires, so replenishing the sealant will help to fill the holes.
Tubeless tires, which do not require sealant when inflating, have no sealant inside the tire. If the cause of a puncture in a tubeless tire is a small hole (also known as a pinhole puncture), the hole can be sealed by replenishing sealant. Depending on the size of the hole and how it tears, sealant may not be sufficient to repair the hole.
In the case of tubeless ready tires that have already been refilled with sealant, the sealant inside the tire should fill the hole when the tire is punctured, so in many cases, the hole may not be able to be sealed with sealant.
In such cases, you will need to take a different course of action.
Fill the hole with a repair tool
There are special repair tools for tubeless tires. There are two types of repair tools for tubeless tires.
- a patch that is placed over the tire
- a patch that fills the hole
In the case of tubeless tires on road bikes, type (1) is often used. It is very easy to apply the patch to the tire without removing the tire. However, since the area where the patch is applied must be flat, it can only be used on slick-type tubeless tires.
On the other hand, the type used on block tires, such as MTB tires, is the type that plugs the open hole. Using a special tool, the repair strip is inserted into the hole and the hole is plugged.
Larger tearing holes cannot be repaired, but if the hole is only a few millimeters in diameter, the repair strip will seal the hole and the sealant will fill the gap. This repair can also be done while the tire is still mounted.
|Compatible tires||Tires for low-pressure operations, such as MTB and gravel bike tires|
If you have a large crack or hole that cannot be repaired with a repair kit, one option is to give up on repairing the tire and go with a tubed tire, since most tubeless tires can be used as clinchers if a tube is inserted inside.
However, even if the tire is tubed, the situation is the same with a hole in the tire, so if the air is inflated at high pressure, the hole may cause the tube to puncture, so the pressure should be low.
In addition, the process of converting a tubeless tire to a tubed tire is a different process than changing the tube on a clincher.
Tubeless tires are constructed with a bead that fits tightly into the rim, so it is often moderately difficult to remove the tire and insert a tube while on the road. If you are going tubed to repair a puncture in a tubeless tire, make sure you carry not only a replacement tube but also a tire lever that is compatible with tubeless tires.
In terms of work, it is also helpful to carry thin rubber gloves and a garbage bag in your tool bottle or saddlebag, as the sealant inside a tubeless ready tire can splatter when you remove the tire, and your hands can get covered in sealant.
Another option is to use tire inserts, in the sense that if a tubeless tire goes flat, it can only hold air while you make it home.
Items mentioned in this article
LEZYNE Bar Insert Tubeless Tire Repair Kit
Manufacturer Lezyne Compatible tires Tires for low-pressure operations, such as MTB and gravel bike tires