Road bikes and cross bikes generally have narrow tires.

• While it may seem that they are prone to punctures, they are actually not.

If they do seem prone to punctures, there is a reason.

Below, we will explain the causes of punctures in road bikes and how to prevent them, so please use this as a reference.

Punctures from foreign objects

Generally, punctures caused by foreign objects are the most common type of puncture.

When riding on the road, nails or other objects can pierce the tire, creating a hole in the tube and causing air to leak out.

The holes are often round.

Sometimes they are "pinholes" (holes about the size of a needle prick).

The rate of tire pressure loss is proportional to the size of the hole.

As a countermeasure, there is not much you can do except to always pay close attention to the road while riding.

When riding, you should look ahead, but also keep an eye on the ground and avoid any foreign objects.

Most people probably already do this, but on rainy days, it can be difficult to distinguish between different ground colors.

For this reason, there are even statistics showing that punctures are more common on rainy days.

On rainy days, various objects can wash into storm drains, so always try to avoid puddles.

Pinch flats (rim strikes)

When you hit the front wheel while going over a bump, the rim presses against the tube, creating a V-shaped hole.

In the puncture industry (if such a thing exists), this is called a "snakebite," and the shape alone is enough to identify the cause.

As a countermeasure, pinch flats are more likely to occur when tire pressure is low.

Maintaining the correct pressure will allow the tire to absorb small shocks, such as mounting a curb.

If you are riding a road bike or cross bike, you will be traveling at higher speeds, which can be dangerous. It is much easier, safer, and helps prevent punctures to ride on asphalt roads rather than sidewalks whenever possible.

Spoke puncture

Punctures can occur due to the deterioration of the rim tape.

The part that acts as a nut to secure the spokes is called a "spoke nipple," which has a negative screwdriver groove.

With rim tape, it should not come into contact with the tube, but punctures can occur if the rim tape deteriorates or shifts.

When it deteriorates, it stretches and becomes more prone to shifting.

As a countermeasure, replace the rim tape when it shows signs of deterioration.

If you ride your bike frequently, it's a good idea to replace it about once a year. If you only use it for commuting or schooling about 5 km one way, then checking it during a puncture repair or every 3-4 years and replacing it if it shows deterioration should be sufficient.

When replacing rim tape, you need to check the size beforehand as there are different sizes.

The most commonly sold rim tapes are generally 16mm to 18mm wide.

Be careful with types that have wider tires, such as mountain bikes.

Tape-type rim tapes are easy to apply, so you can do it yourself.

They are also convenient because you can choose the firmness, but repeatedly reapplying them can make them peel off easily, so some practice may be required.

Band-type rim tapes are highly durable.

Since they are in a loop, they are less likely to shift.

For stiffer ones, it's sometimes better to have two people work on it.

Tiny pinholes

Unlike pinholes caused by something puncturing the tire, these holes can be difficult to find, and the symptom is that the tire loses air within one to two days.

Amateurs may not be able to find the hole even after attempting a puncture repair.

Some people feel as if the tire is losing air even though it hasn't punctured.

There are various causes, such as something puncturing the tire, fraying wires inside the tire piercing the tube, shifted rim tape, shifted tube, or shifted valve.

Burst

Under normal riding conditions, a burst tire is extremely rare.

A tire bursts when it is ridden even after being worn down.

In addition, when repairing a puncture, if the tube is pinched between the rim and the tire, it will burst relatively quickly.

To prevent this, you should replace the tires when the tread is worn down, and be careful not to pinch the tube between the rim and the tire when repairing a puncture.

The timing for tire replacement is determined by the mileage.

Generally, the lifespan of tires on sports bikes like road bikes is said to be 3000km to 5000km as a guide for replacement.

For city bikes and light bicycles (mamachari), it is generally considered to be about 3 years.

Summary

While it's simply called a tire puncture, for bicycles, there are about five different patterns.

While "punctures from foreign objects" and "pinch flats" are common, both can be largely prevented depending on how you ride.

Road maintenance has improved recently, so there are fewer nails on the road. Avoiding forcefully going over bumps will significantly reduce the chance of a puncture.

External Writer: Koichi Okuno