German-made Rail Grinder on the Keio Line

Keio’s rail grinder, ROMILL 600DT (“ROMILL Supply” side)

Are working vehicles popular among children in your country?

In Japan, they are very popular. According to several popularity polls, police cars rank first, followed by fire engines, excavators, ambulances, and many others. A wide variety of picture books on working vehicles are also published for young children.

How about working vehicles that run on railway tracks?

To be honest, except for the famous “Dr. Yellow” on the Tokaido–Sanyo Shinkansen, railway working vehicles are not very well known, mainly because they tend to go unnoticed. Even so, curious children will quickly gather whenever an unusual railway vehicle appears. I recently witnessed such a scene near the Sakurajosui railyard on the Keio Line. I followed the children who had gathered there, and eventually found what they were looking at.

Please take a look at the photos—this is a rail grinder, the ROMILL 600DT, parked on a siding. Keio Electric Railway introduced the ROMILL 600DT from the German manufacturer Robel in January this year. With this addition, Keio became the first Japanese private railway company to operate a milling-type rail grinder. European manufacturers indeed have a strong presence in this field.

The ROMILL 600DT consists of two diesel-powered cars: “ROMILL Work” and “ROMILL Supply.”

The former includes a rail-milling unit with cemented-carbide tips, a polishing unit, and an inspection unit. The latter provides a workspace for replacing milling inserts and also houses a fuel tank.

Why did Keio introduce the ROMILL 600DT?

First, for safety: milling and grinding help prevent rail damage and provide passengers with a smoother, more comfortable ride. Second, for cost efficiency: maintaining rail surfaces properly can significantly reduce long-term maintenance expenses by preventing serious rail defects.

As a rail fan, I am genuinely fond of the ROMILL 600DT. Its blue-and-red two-tone body looked especially beautiful in the spring sunlight. I would love to watch it in operation someday, but that is quite difficult, as it usually works only after the last train has finished for the day. Moreover, Keio does not publish its operating schedule.

Even so, I hope the ROMILL 600DT continues to do great work behind the scenes.

ROMILL 600DT ("ROMILL Work" side)

Related link:

• Official information from Keio (in Japanese)

• Official video from Keio (in Japanese)

Final Chapter of the 6000 Series EMU in Indonesia

Set 6117 of the 6000 series EMU in Jakarta, Indonesia

Photo: Faris Fadhli (2026)

Today, I’d like to share a little story about Indonesia’s railways.

Not long ago, I received a heartwarming message from an Indonesian railfan. My friend, Faris Fadhli, sent me some updates along with his latest photos. I always enjoy hearing from him—his messages make me feel closer to Indonesia’s railway scene. After reading his note, I felt inspired to write about an “endangered species” that has long fascinated me.

Please take a look at the photo above. It shows the endangered ex–Tokyo Metro 6000 series EMU running in Jakarta, Indonesia.

The 6000 series is a 1,500 V DC commuter EMU that first entered service in Tokyo in 1968. In total, 36 sets—353 cars—were built through 1990. Its technology was considered advanced at the time, equipped with an armature-chopper traction system and regenerative braking. Many sets were later upgraded with a VFD (Variable Frequency Drive=VVVF) traction system and induction motors.

After 43 years of service in Tokyo, 27 sets were transferred to Jakarta starting in 2011, helping modernize the commuter lines operated by PT Kereta Commuter Indonesia.

Now, let’s take another look at the recent photo. A red-striped 6000 series train stands out under the tropical sunlight, framed by lush greenery. Beautiful! I instantly recognized the spot—Universitas Indonesia Station, a classic place for train photography. Faris’s photo brought back many memories from the time I was stationed in Indonesia.

I also vividly remember the excitement in 2011, when the 6000 series first arrived in Jakarta. I was extremely busy with work then, so Indonesian railfans, including Faris, visited Bukit Duri Railyard and kindly shared their photos of the newly arrived trains with me (see the photo below). It’s hard to believe that fifteen years have passed. Time truly flies.

I’m glad the 6000 series is still active in Jakarta. However, according to Faris, the trains are now being gradually phased out as the new Indonesian-built CLI-225 series enters service. Panta rhei—everything is constantly changing.

The final chapter of the 6000 series has already begun.

Set 6126 of the 6000 series EMU (right) upon arrival in Jakarta, Indonesia

Photo: Faris Fadhli (March, 2011)

New LEO LINER on the Yamaguchi Line

Seibu L00 series EMU, LEO LINER (Set L11)

Today, I would like to introduce a new train model in the Tokyo metropolitan area: Seibu Railway’s L00 series EMU, called the LEO LINER, for the Yamaguchi Line. This new model entered service on March 27 and replaces the older 8500 series EMU.

First, let me briefly introduce the Seibu-Yamaguchi Line.

The line is a rubber-tyred automated guideway transit (AGT) system that runs across the border between Tokyo Metropolis and Saitama Prefecture. It connects Tamako (Lake Tama) and Seibu-Kyujō-mae (Seibu Baseball Stadium) stations, and its total length is only 2.8 km. The entire route is single-track and uses a 750 V DC third-rail power supply. Unlike other AGT lines such as the Seaside Line, and the Nippori-Toneri Liner, trains on this line are operated by a driver. It is not a driverless system.

The top photo shows the L00 series. Each trainset consists of four aluminum-alloy cars, each 8.5 meters long (two motor cars and two trailer cars). The traction system uses variable frequency drives with 110 kW induction motors. One of the differences from the older 8500 series is that the L00 series has double-leaf external sliding doors. Seibu Railway plans to introduce three trainsets of the L00 series by the end of March 2028.

My first impression was that it looks similar to the Yurikamome 7500 series EMU. It also reminds me of JR East’s HB-E220 series. The polygonal shape of the front of the train seems to be a trend in the design of recent rolling stock.

Regarding the interior, please look at the photo below. There is a transverse seat located just behind the driver’s cab. It is called the “Kids Seat,” and it is designed for a parent and a child. They can enjoy watching the driver operate the train and looking out the front. Recently, more Japanese railway companies seem to be installing special seats for parents and children, and I think this is a very good idea.

I enjoyed observing Seibu’s new LEO LINER very much.

“Kids Seat” in the L00 series train

Related link:

・Official information from Seibu Railway (in Japanese)

・Official video from Seibu Railway (in Japanese)

Classic DMU on the Joso Line

KiHa 0 series DMU on the Joso Line

This may sound a little sudden, but are you an early bird or a night owl?

As for me, I’m definitely the latter. I usually get up late, especially on weekends. In Japan, people like me are often thought to be lazy, which feels a little sad.

Still, even I have exceptions. Please take a look at the top photo. You can see the classic KiHa 0 series DMU of Kanto Railway running on the Joso Line. I took this photo early morning because this train operates only at that time. For once, the early bird really did catch the worm!

■ What Are Kanto Railway and the Joso Line?

Kanto Railway (often called Kantetsu) is a local railway company in the northeastern part of the Tokyo metropolitan area. Its Joso Line runs through Ibaraki Prefecture from south to north, connecting Toride and Shimodate stations over a distance of 51.1 km. Toride provides an important transfer to JR East’s Joban Line (see the photo below).

Kantetsu has a unique atmosphere—a mix of a commuter line and a local rural line. As shown in the top photo, the section near Toride is double-tracked, and trains run every nine minutes during the morning rush. However, the line is non-electrified, and most trains consist of only one or two cars.

■ Rolling Stock Notes: DMU KiHa 0 Series

The KiHa 0 series DMUs entered service in 1981. Each trainset consists of two 20-meter-long, single-cab cars. A total of four sets—eight cars—were built using equipment reused from the Japanese National Railways KiHa 20 series.

■ Details Trainspotters Will Enjoy

If you feel like you’ve seen this railcar somewhere before, you have a sharp eye for Japanese trains. The KiHa 310 series, which I introduced in 2011, looks very similar to the KiHa 0 series. However, if you look closely, you’ll notice some differences. For example, the shape of the front destination display is slightly different, and the presence or absence of rain gutters on the sides also varies. Did you find the differences?

Toride Station on the JR East Joban Line and the Kantetsu Joso Line

Related Link:

・Official information from Kanto Railway (in Japanese)

New Model on the Urban Park Line, Part 2

Trainset 81551 of Tobu’s 80000 series EMU at Nanakodai Railyard

You may remember that I wrote about Tobu’s 80000 series new EMU last June. At that time, I mentioned that I would “save the technical specifications of the 80000 series for a future post.”

Ten months have passed since then. Time really flies. Now, I finally have a chance to introduce those details, so let’s get started.

The 80000 series EMU is Tobu Railway’s commuter train for the Urban Park Line (Noda Line). It operates on a 1,500 V DC system with a 1,067 mm track gauge. The train entered service in March 2025 to replace the older 8000 and 10030 series. Each set consists of five 20-meter cars—two motor cars and three trailer cars. The car bodies are made of aluminum alloy, and a total of 25 sets are planned to be introduced.

Here are some of the technical features.

First, the train is equipped with 250 kW synchronous reluctance motors instead of the conventional induction motors. The traction system uses a full-SiC VFD (full silicon-carbide variable-frequency drive). These technologies help reduce maintenance and save energy.

Second, the train has an on-board battery system. The power generated from regenerative braking is not returned to the overhead lines but stored and used for on-board power supply. This helps prevent the loss of regenerated energy.

Third, two trainsets are equipped with monitoring equipment for facilities such as tracks and overhead lines.

Now, I would like to share a topic for old-school trainspotters as well. Please take a look at the top photo. I took this photo of the 80000 series when I joined an event held by the Japan Railfan Club at Nanakodai Railyard. This particular trainset is slightly different from the one I showed in my post last year.

Please look at the photo below. The middle car (Car 3, SaHa 83551) looks different from the cars on both sides. For example, the height of the roof and the shape of the lower body seem a bit unusual.

In fact, this car is a refurbished vehicle from the 60000 series EMU, not a newly built one. Why did Tobu choose to do this?

I’m running out of space here, so I will save the explanation for a future post. Please look forward to it!

Car 3 (SaHa 83551) of trainset 81551

Related link:

• Official information from Tobu Railway (in Japanese)