[Test Ride Impression] SR400 Legendary Tasty Single Heart

SR has been existing in the world since I first obtained the license, and still been keeping it running and supported by fans. The word, “SINGLE” was not that common when SR was first released so it drew people’s attention. SR once became very popular among young riders due to its reasonable price, and it triggered a boom in customized motorcycles.

Now SR is facing a big turning point. SR has equipped FI engine. SR’s air-cooled engine used be so simple that it was nearly seen in a school textbook. Now around cylinders and exhaust pipes there are extra pipes added. They are sensors, a fuel pump, and some duct works for FI. This made me a little sad.

However, SR survived. That fact is more important than the change.

The tank is in deep black and has narrow lines. This classical coloring on the tank is a real art work of Showa era. It is beautiful and has an atmosphere. There is not a motorcycle but SR to be laden with history.

It is kick-start only. Its start-up performance gets a passing mark easily in consideration of the fact you need to kick two or three times to start up when the temperature is below 0℃.

This is what we call the power of FI… Wait a minute. There are more modifications on new SR. Torque at 4000-5000 RPM got increased. It feels like more powerful than before.The peak torque shown on the chart in the catalogue is lower than that, but its demonstrating rpm is also lowered. I am not sure if the peak torque is cut out, or low rpm range is more powerful. However, new SR is more persistent and better at accelerating than former SR.

Although SR has gone through several changes such as cast wheels and front drum brakes, SR has let the time pass without having major changes in its style since 1978. Each part has its own beautility and riders will never get bored with it.
This beautiful air-cooled single now has a full transistor ignition system. This change is made from this model. It reduced its operation load by 30% by changing the clutch spring. The peak power shown on the specification went down, but it does not bear comparison with the ride before because now the torque at a middle speed range is increased.
The catalyzer is now built-in, and the silencer comes with a heat guard and is slightly thicker than before. It is coated with nano film to avoid color discoloration and deterioration due to burnt. These changes are made from this model.
The biggest change of this model is having FI. It is loaded with 12-hole injector which has great atomization characteristics. It also made it realize to have high-responses by the combination of newly designed throttle body and throttle position sensor.
An AI (air injection) unit is also installed accompanied with FI to contribute the emission control. The unit is installed underneath the throttle body.
Fuel pump is located inside of the side cover not to interfere the beautility and the capacity of the tank. The size of the unit is rather big since this is a sub-tank.

I can say that it became quieter and lost the roughness I used to feel instinctly, but it has the most linear response I have had among SRs in last 5 years. It is much better to control the fuel deposition by programing using FI than to struggle with a carburetor to deal with the sound and the emission regulation.

I almost forgot to tell you how I feel when I am on it. SR is a real classic model. Handling has been basically the same as it looks for last 30 years.

“First of all, the fork, the frame, the swingarm, and the tires are all flexible. They all response gently with just a little bit of heavy reaction comparing to current XJR400 and XJ6. This is not what we call “”dull””. Very gentle response. The whole chassis is flexible and has a gentle maneuverability, so that you are required to operate the brake and throttles with a care. In another words, it is preferable that you open and close throttles in tune with SR’s unique rhythm to go along with the suspension ‘s gentle move.

Recent motorcycles balances out naturally or on their own to a certain riding point. You may want to to remember that if you ride a SR. If you know that, SR will be your dutiful partner. It does not have strong turning characteristics, but its handling is textbook-perfect. You can enjoy it at leisure blissfully.

A fuel pump is built-in and a side cover is changed to be 10mm flared. The emblem of SR is now made of metal to emphasize its texture
Classicaly designed white dials are adopted. A fuel warning lamp is added on lower indicators due to the change to FI.
A simply designed long seat will enhance the flexibility of riding positions. The shape is basically the same as before.
Black anodized color of the bake caliper will give a neat impression at feet of SR. The inner rotor of the brake disk is also in black anodized.
The size of front/rear tires are the same as before. Tires used are Metzeler made, as usual. The side stand is newly designed focusing on the operability.
The upper body tilts slightly forward, that way you can relax as if you are sitting on a chair .There are several options for seat positions, so you can choose the best seat position for the best comfortability. It also has an adaptivity to be suitable for not just street use but also for a long ride. When it comes to cornering, needless to say, it goes perfectly with “lean with”. That is how I could get the best response.

Original Source [Autoby] (*Japanese)

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