Bicycles are constantly evolving these days.

Road bikes, in particular, are becoming lighter and lighter, and you'll surely feel their speed just by riding them.

By the way, professional road bike racers reportedly reach speeds of over 70 km/h.

Even amateur riders, if they're fast, can reportedly reach around 60 km/h.

This leads to a slight concern: speeding on a bicycle. Will it count as a "speeding violation"?

■No Speeding Violations

Under the Road Traffic Act, bicycles are classified as "light vehicles."

However, there is no mention in the law regarding the speed of light vehicles.

In other words, no matter how fast you ride a bicycle, it won't count as a speeding violation.

However, please only speed where it's safe to do so.

If you can speed on a bicycle, you might wonder how fast you're actually going.

That's where the topic of a speedometer comes in.

Should you install a speedometer?

■Smartphones make it easy to track routes and speeds later.

Actually, you don't really need a speedometer.

These days, with smartphones, it's easy to check your route and speed later.

Google Maps has a "Timeline" feature that records your movement patterns using GPS information.

You can check which roads you took and where you went, going back several years.

If you set up the speedometer feature, you can also display your speed.

■Self-Satisfaction

A speedometer is basically for self-satisfaction.

After all, there's no concept of obeying a speed limit since there's no speed limit for bicycles.

A speedometer exists for you to confirm to yourself, "I managed to go X kilometers per hour!", making it mostly a world of self-satisfaction.

And there's nothing wrong with self-satisfaction.

Bicycles are originally for personal use, a whole package of self-satisfaction.

With that in mind, I'd want a cool speedometer.

■Aftermarket wiring is unsightly

If you go to a store to look for a speedometer, you'll find everything from inexpensive ones starting at around 800 yen to camera-GPS integrated models costing over 50,000 yen.

I thought a cheaper one would be good, but when I looked into it, I found a major weakness.

The mechanism of a speedometer involves attaching a magnet to the spoke and a receiver to the front fork.

Each time the tire rotates, the receiver detects it and receives the distance information.

Knowing the time and distance allows you to calculate speed using the formula you learned in junior high school.

It's simple, so if you set it up properly, you can measure speed relatively accurately.

It's durable, which is good, but the wiring from the handlebars to the front fork is unsightly.

No matter how neatly you wire it, it just doesn't look good.

High-end models have GPS, so there's no wiring to the tires, but I'm a bit skeptical about the accuracy of GPS.

When riding in a straight line, it feels like the speed display is slightly delayed.

■Just buy a smartphone holder and you're good to go.

Speedometers are expensive, and all you get is information that isn't very accurate.

I don't recommend magnet-type speedometers because the wiring is unsightly.

Perhaps it's best to think of them as something to try out and enjoy.

Instead, why not look for a smartphone holder?

There are many available for cars, but relatively few types for bicycles.

You can buy one for around 2,000 to 3,000 yen, so if you think you need one, try looking for it.

The trick is to choose a sturdy one so you don't drop your precious smartphone while riding.

There are free apps for speedometers and dash cams on smartphones, so having a smartphone might make you invincible.

■Summary

Speedometers don't provide very accurate values.

If you understand that and your goal is to know your approximate speed, then it's fine.

While it's good to install a dedicated device, simply buying a smartphone holder and attaching your phone might fulfill your desires.

Maps, speedometers, dash cams—most of what you want can be achieved with a smartphone.