This Japanese motorcycle engine is so reliable that it is still in production after more than 25 years

In general, Japanese manufacturers have been more willing to push technical boundaries when it comes to experimenting with different types of engine configurations. We have seen all kinds of different engines come into production. From rotary engines to square fours, to V4s, to inline sixes, and from two-strokes to four-strokes, we’ve literally seen it all.

Although European and American manufacturers tend to stick to one engine type, we have always been blessed with variety from the Japanese. Of course, this level of research and development came at a cost, but it’s fair to say that all of these manufacturers have recouped that investment, and in some cases come close to perfecting the internal combustion engine. One of those engines is a trusted little twin of Suzuki.

In order to provide you with the most current and accurate information, the data used to compile this article was sourced from Suzuki bicycles. While the opinions are ours.

Suzuki’s 645cc V-Twin is so reliable it’s still in production after more than 25 years

Power: 64 to 75 hp

To be fair, there are actually several Japanese motorcycles that have been around for decades. But few can compete with modern motorcycles like Suzuki’s old 645cc V-twin. Suzuki is a master at extending the life of engines and refuses to let good tools go to waste. By maximizing the R&D put into older engines, the brand can pass these cost savings on to the customer. As a result, we can find a wide selection of Suzukis that offer great value for money.

All these efforts to keep it in production would be worthless if there were no demand or reliability concerns. With these twins, the only issues that appear on forums literally have to do with poor maintenance. These motorcycles have been raced, taken to all corners of the world and used for commuting for years.

As long as you take care of basic maintenance, they simply won’t let you down. The simple fact that Suzuki has gone to great lengths to get it through the Euro5+ emissions regulations only underlines that there is still demand for it too. Even with the added emissions controls it can still deliver good power, with the latest version producing around 72bhp.

The Suzuki 645cc V-Twin is a versatile powertrain

With a bore and stroke of 81 x 62.6 mm, this is an oversquare engine. The result is that it’s free-revving and peak torque is a little higher in the rev range, but most of it is still available from around 3000rpm, translating into a wonderfully flat torque curve. This is ideal for real driving conditions, where we are bound by speed limits and stretches of poorly maintained roads. This midrange performance is exactly what all modern crossplane parallel twins strive for, but you don’t need an engine to emulate a V-twin if you already have one.

Famous V-Twin models

The versatility of this powertrain has led Suzuki to house it in two very different model lines over the years. It all started with the original SV650 in 1999, but demand for a sportier version quickly grew. This resulted in the production of the popular SV650S (pictured), which featured a bikini fairing and lower handlebars. The latest SV650 has a better chassis, but stays true to the original by keeping it quite simple.

In 2004, the demand for a lightweight touring model grew and this gave rise to the now famous V-Strom 650. Over the years, this small touring motorcycle has evolved into a full-fledged adventure bike. Although the V-Strom 650XT (pictured) will soon be phased out, it remains a popular ADV thanks to its impressive versatility.

The Suzuki 645cc V-Twin appeals to riders of all levels

One of the things that really makes this powertrain stand out is how accessible it is. There are a number of things that go into making a great motorcycle, and having an engine that is easy to use is an important part of the puzzle. It builds revs in a smooth, predictable manner, allowing novice riders to learn without being punished.

It’s also tractable enough for more experienced riders, as it performs admirably within its sweet 3,000 to 6,000 rpm range. While not necessarily a beginner-friendly drivetrain, both the V-Strom and SV650 are fantastic motorcycles that new riders can upgrade to.

These aging twins still have a bright future

Speaking of which, it looks like the V-Strom 650 line will finally bid us farewell. The V-Strom 800 bikes are all great, and that parallel-twin makes a lot more sense on an adventure bike platform. However, the 650 is far from ready. The SV650 has indeed made it to 2026 and continues to give us an affordable, fun option for a Naked Bike that is the spitting image of the original Ducati Monster – widely regarded as the first Naked Sports Bike – and that’s not a bad thing at all.

Suzuki is also all set to launch a new light-duty crossover, in the form of the SV-7GX. It will offer all the modern features that the bare-bones SV650 doesn’t, bringing this likeable powertrain into the modern era. While some were surprised that this new crossover didn’t have Suzuki’s 800, that wasn’t the case with us. It will extend the life of the V-twin even further, offer buyers even more value and, thanks to the fact that it will use the SV650 chassis, also be a fun bike to ride.