The Honda NT650 Hawk GT (RC31) is one of those rare motorcycles that was truly appreciated only years later. When Honda introduced it in the late 1980s, many riders didn’t quite understand what they had in front of them. The Hawk GT was relatively expensive for a 650cc naked bike and had less power than many four-cylinder competitors. What many people didn’t see at the time was that Honda had built a technical masterpiece that was ahead of its time.
As a result, the Hawk GT was not a sales success but grew into a true cult classic. Today, the RC31 is regarded by enthusiasts as one of the most special Hondas ever built. Not because it was the fastest or most powerful, but because Honda developed a motorcycle focused on riding pleasure, technology, balance, and durability.
The heart of the Hawk GT is the well-known 647cc 52° V-twin. This is the same basic design Honda used for the legendary XRV650 Africa Twin RD03. While the Africa Twin was developed for adventurous rides and Dakar influences, the Hawk GT received a sportier setup for road use. The result is a characterful engine with plenty of low-end torque, smooth power delivery, and a reliability reputation that is almost unmatched.
That’s no exaggeration. Mileages of 300,000 to even 400,000 kilometers are not uncommon when regular maintenance is performed. The NTV, Revere, Hawk, and Africa Twin engines are among the most durable V-twins Honda has ever built.
But what really makes the Hawk GT special is the chassis. Honda applied a lightweight aluminum twin-spar frame at a time when many competitors still used steel tube frames. The inspiration came directly from the VFR750F, which had earlier introduced an aluminum twin-spar frame. However, in the Hawk GT, this concept was applied to a significantly lighter and more compact motorcycle. With a dry weight of about 168 kilograms, it became a machine that handled exceptionally nimbly and still impresses modern riders.
Additionally, the Hawk GT features Honda’s iconic Pro-Arm single-sided aluminum swingarm. The exclusive VFR750R RC30 had this design earlier, but that was an expensive homologation special out of reach for most riders. The Hawk GT brought this technology to a regular production street bike and showed that advanced chassis designs were not reserved solely for superbikes.
The influence of this design is still visible today. Honda later used the Pro-Arm on various VFR models, and Ducati was clearly inspired by the concept as well. The single-sided swingarm eventually became one of the most recognizable features of iconic models such as the Ducati 916 and Ducati 748.
Even when you look at the later Honda VFR400R NC30, you see the same design philosophy: a compact aluminum chassis, a single-sided swingarm, and maximum riding characteristics within a relatively modest displacement. The Hawk GT fits perfectly within that line of technically advanced Hondas built by engineers rather than marketers.
What may be even more impressive than the technology is the reliability. The Honda NT650 Hawk GT is known as one of the most trouble-free motorcycles of its generation. The bike actually has no structural weak points.
Two parts are often mentioned when it comes to known Hawk GT issues: the voltage regulator and the Fuel Pump. In reality, these are normal wear parts that reach the end of their lifespan after decades of use.
The original voltage regulator often fails somewhere around 60,000 kilometers. Fortunately, an excellent solution is available in the form of the Carmo MOSFET voltage regulator. This modern voltage regulator works more efficiently, runs cooler, provides a more stable charging voltage, and is also suitable for modern lithium batteries such as the Shido HP (High Performance).
Especially on the Hawk GT, a combination of a lithium battery and a MOSFET voltage regulator is a very popular upgrade. The V-twin engine demands relatively much from the battery during starting and noticeably benefits from the higher starting capacity of a modern lithium battery. The result is faster starts, less strain on the electrical system, and a more reliable starting procedure.
A part often overlooked on the Honda NT650 Hawk GT is the rear sprocket carrier dampers (cush drive rubbers). These rubber dampers sit between the rear wheel and the sprocket carrier and are designed to absorb shocks in the drivetrain. This makes gear changes smoother, reduces load peaks, and maintains riding comfort.
After decades, the original rubbers harden, shrink, or crumble somewhat and lose their damping effect. The result is extra play in the drivetrain, a less refined feel when opening and closing the throttle, and more stress on the chain, sprockets, and transmission.
Checking is simple. Remove the rear wheel or hold the rear sprocket carrier and try to twist it relative to the wheel. Minimal movement is normal, but the sprocket carrier should have hardly any play. If you can clearly twist the sprocket carrier without the rear wheel moving immediately, the dampers usually need replacement.
New rear sprocket carrier dampers ensure the drivetrain feels tight again as Honda originally intended. Gear shifts become smoother, load change reactions decrease, and the bike feels noticeably more refined during normal street use.
Since most Hawk GTs are now over 30 years old, these rubbers are among the parts that almost always deserve attention when you want to bring a bike back to optimal condition.
Another popular upgrade is the Carmo CDI Unit. The original Honda CDI Units are now over thirty years old and can become sensitive to age-related issues.
The modern Carmo CDI not only offers a reliable replacement but is also technically improved. The unit features an optimized ignition curve, a more precisely controlled spark, battery voltage compensation, overvoltage protection, and a special start mode that provides a stronger spark during starting.
Additionally, the adjusted ignition curve delivers similar benefits as the well-known Factory Pro 4-degree ignition advance modification (no longer available!), but electronically controlled and much more precise. This results in better starting, quicker throttle response, and smoother running throughout the entire rev range.
When a Hawk GT experiences fuel problems, a faulty Fuel Pump is often suspected immediately. In practice, however, it usually turns out that the contact points inside the original pump are worn out.
These contact points are available separately and can be easily replaced. This is usually a much better solution than installing a cheap replacement pump.
In fact, the original Honda Fuel Pumps built over 30 years ago often still prove to be of higher quality than many modern budget alternatives. Simply by replacing these contact points, the original pump can often function trouble-free for many more years.
Those who want to get the most out of the Hawk GT eventually turn to the carburetors. The Factory Pro jet kits have been among the most popular upgrades for the RC31 for years.
With adjusted needles, improved tuning, and more precise fuel delivery, the engine responds faster to the throttle, runs smoother, and the characterful V-twin engine comes into its own even better. Combined with a Carmo CDI and a well-tuned air filter setup, this creates a surprisingly modern riding experience without losing the engine’s character.
On this page, you will find a carefully selected range of parts and upgrades for the Honda NT650 Hawk GT (1988-1991). From Carmo CDI Units and MOSFET voltage regulators to Fuel Pump parts, carburetor upgrades, maintenance products, and high-quality accessories.
The Honda NT650 Hawk GT may not have been a sales hit when it was new, but precisely because of that, it is today one of the most beloved cult Hondas ever built.
A motorcycle designed by engineers who wanted to build the best possible engine – not the cheapest.
