For rim brakes, if replacement is needed, simply replacing the brake shoes is usually sufficient.

I've provided detailed information on when and how to replace them in another article, so please check that as well.

When to Replace the Rim Brake Caliper Itself

For rim brakes, if replacement is due to wear, I believe simply replacing the brake shoes is enough.

The guideline for replacement is before the grooves on the brake pads disappear.

If they are less than 1mm, replacement will be necessary.

It's unlikely that replacement will be needed in less than a year, even at the earliest, so even if you ride the same bike for 10 years, a few brake shoe replacements should suffice for most needs.

However, if you want to upgrade, that's a different story.

Brake Upgrades

Even when talking about brake upgrades, it's generally not possible to change caliper brakes to V-brakes.

Most bike shops probably won't accept such a request.

The base structures are different, so they cannot be installed.

There are bicycle modification enthusiasts out there who might manage to swap them, but they are a minority.

However, replacing caliper brakes with other caliper brakes, or V-brakes with other V-brakes, is possible.

When you replace brakes, it's typically when you want to upgrade them.

More specifically, it's when you want to improve safety.

For mini velos or city bikes ("mamachari"), the top speed is around 25 km/h.

However, for road bikes, even a beginner riding in the city can relatively easily reach 30 km/h.

Once you get used to it, you can ride even faster on a road bike.

Since road bikes can travel at speeds similar to or greater than mopeds, a certain level of stopping power is required.

Is a Brake Upgrade Necessary?

When riding a bicycle, you probably rarely think that your brakes aren't working effectively.

However, once you experience a "firm" stop while test riding at a bike shop or borrowing a friend's road bike, you might realize how ineffective your own bike's brakes are.

If ordinary brakes are used in about three stages: "decelerate," "stop," and "emergency stop," the famous Shimano 105 (Ichimarugo) feels like it offers about seven stages of control, if not ten, for more nuanced braking.

Once you experience this, the desire to improve your brakes will persist, and you'll start researching which ones are good and how much they cost.

Grade Differences Reflect Intended Riding Speeds

So, how do you choose brakes that all seem similar?

If you look for brakes, you'll find a wide range, from cheap to expensive.

In terms of price, I've seen some as low as 1,000 yen and some as high as 60,000 yen.

This difference is due to the intended riding speed.

General brakes are designed for speeds of approximately 15 km/h to 20 km/h.

Professional race brakes are likely designed for speeds of approximately 70 km/h to 100 km/h.

To stop tires at such speeds, the materials inevitably change, and they become larger and shaped to maintain rigidity.

In terms of price, Shimano's 105 has a real-world price of about 8,000 to 9,000 yen, so you'd want to prepare something with performance equal to or better than that.

Beware of Brake Types

As mentioned above, even within rim brakes, there are several types.

Even just among the representative types, there are "caliper brakes," "V-brakes," and "cantilever brakes." Although their mechanisms are similar, they have no compatibility whatsoever, and if you buy the wrong one, you'll have no choice but to buy a new one.

Beware of Different Arm Lengths

Even with the same type of brake, there are various "arm lengths."

Furthermore, there are overlapping parts, which often makes it difficult to decide.

If you know the frame name or model number, I recommend checking the manufacturer's website.

The names and arm lengths are summarized below:

Short arch → 49mm, 51mm

Long arch → 47mm-57mm, 55mm-73mm

There are short and long arches, but even with short arches, you need to look carefully to distinguish between 49mm and 51mm.

By the way, the 105 mentioned above is 51mm.

For long arches, as you can see, 55mm-57mm overlaps, so both can be used, but for longer ones, only those from 55mm-73mm may be compatible.

Recently, attachments that can extend short arches to long arches, and special brake pads, have become available, allowing for an extension of about +10mm.

However, it's best to avoid mistakes, so please confirm thoroughly with the specifications table when choosing.

Check the Manual or Videos Before Replacing

If you're used to it, replacement is a relatively simple task, but manuals, and recently even replacement videos, may be available if you search by model number.

Additionally, volunteers sometimes upload videos to YouTube.

By checking these before starting the work, you can reduce errors and proceed smoothly.

Related article: Rim Brake Replacement Timing Guidelines and Durability

External writer: Koichi Okuno