Following our deep dives into the razor-sharp track geometry of the FireBlade, the naked streetfighter evolution of the Hornet, and most recently, the heavyweight touring Blackbird; it is time to pivot to one of Honda’s most brilliant, yet misunderstood, engineering ambitions of the late 1980s.
In an era when the motorcycle industry was locking horns over fully faired sportbikes and high-rpm inline-fours, Honda’s advanced design groups—the very same minds concurrently working on the legendary RC30 (VFR750R) race bike—quietly kicked off a project with a completely different mandate. Following reliability issues with their early V4 engine lineup, Honda desperately needed to demonstrate their absolute mastery of engineering refinement and chassis design.
The goal wasn't a raw top-speed machine, but rather a premium, lightweight naked sport-standard designed to conquer urban environments and mountain passes alike. When the platform debuted, it defied conventional categorization by marrying a bulletproof, utility-focused commuter powerplant to an exotic, race-bred chassis. It was a bike built for the pure connoisseur of handling.
For collectors, restorers, and Honda enthusiasts tracking frame prefixes, factory configurations, and global market naming schemes, the bike's production run represents a fascinating masterclass in subtle mechanical evolution.
Below is the definitive reference breakdown for the Honda Bros, Hawk GT and NTV 650.
Nomenclature & Market Placement
Depending on where you stand in the world, this specific chassis configuration goes by completely different titles, a detail that often trips up modern parts collectors:
The Honda Bros (Japan / Global Grey Markets): Sold concurrently across two distinct engine classes. The 650cc variant carried the factory code "RC31" (marketed as Product 1), while a 400cc version, factory code "NC25" (Product 2), was tailored specifically to conquer Japan’s strict sub-400cc licensing tier. The latter was also designated as the NT 400.
The Honda Hawk GT (North America): Released strictly as a 650cc model under the "NT650" model designation, though it retained the exact same core RC31 frame DNA.
The Honda NTV 600 / 650 Revere (Europe): Engineered as an unkillable, heavy-duty "gentleman's express" and a favourite among high-mileage couriers. Honda swapped the chain out for a low-maintenance enclosed shaft drive, traded the lightweight aluminium frame for a heavy diagonal steel bridge frame, and bolted on a massive 19-liter touring fuel tank (up from the Bros / Hawk's tiny 12 liter fuel tank).
Positioned awkwardly between basic commuter bikes and flagship race replicas, the model line cradled a 52-degree, liquid-cooled, 3-valve-per-cylinder V-twin in a massive, highly rigid aluminum twin-spar box frame. To complete the premium package, Honda equipped it with an Elf-designed "Pro-Arm" single-sided swingarm—a component usually reserved for exotic endurance racers. Elf was a constructor for Formula 1, so this was very impressive for a "commuter" bike! Because of these ultra-premium chassis components, it was incredibly expensive to build. In western showrooms, it commanded a price tag nearly identical to 600cc inline-four sportbikes, leading to slow early sales but guaranteeing its eventual cult classic status.
Generation 1: The Braided-Line Early Era (1988 - 1988)
The first iteration of the platform was a pure celebration of industrial design, intentionally showcasing its mechanical components without bodywork to mask the engineering.
To feed the top end of the twin-spark, 3-valve heads, Honda opted for external, braided oil lines that ran visibly up the rear cylinder. The front suspension utilized a traditional 41mm fork layout but housed a 4-hole damper rod configuration setup inside to manage front-end dive under heavy braking. Additionally, the twin-piston front brake caliper featured exposed mounting slide pins without protective caps.
Visually, Japanese domestic market Bros models stood out with premium brushed aluminum clip-on handlebars and understated, sleek silver component finishes, while export models adapted slightly different finishes to meet Western tastes.
In Europe, the bike debuted as the premium NYV 650 Revere (alongside a tax-restricted NTV 600 in specific markets). These early European bikes were premium-tier builds, characterized by high-end cast aluminium clip-on handlebars, complex instrument clusters, dual horns, a center stand, and a uniquely stubby, low-slung exhaust silencer that left the single-sided Pro-Arm rear wheel entirely exposed.
1988 Honda NT 400 Bros (NT400J): PB184 Granite Blue, NH124 Achilles Black & R114 Wineberry Red
1988 Honda NT 600 (NTV600J): NH119 Tempest Gray, NH193 Crystal White & R107 Bourgogne Red
Generation 2: Suspension & Caliper Revisions (1989 - 1990)
By 1989, Honda began quietly refining the front-end dynamics of the machine to improve low-speed damping feel and ease of maintenance for dealership mechanics.The headline change occurred inside the front forks, where the damping rods were completely redesigned from the original 4-hole arrangement to a 2-hole configuration, significantly changing how the fork oil flowed through the valves during aggressive compression. Externally, the front brake caliper received a minor update, introducing protective screw-on plastic caps to prevent road grime from locking up the slide pins.
In the North American market, low sales figures prompted a total consolidation of options, reducing the entire catalog down to a single, bold hue.
1989 Honda NT 400 Bros / Bros Type II (NT400K / NT400K II): PB184 Granite Blue, NH124 Achilles Black & R114 Wineberry Red
1990 Honda NT 400 Bros / Bros Type II (NT400L / NT400L II): NH1 Black & R107 Bourgogne Red
1990 Honda NT 650 Bros / Bros Type II (NT650L / NT650L II): NH1 Black & R107 Bourgogne Red
1989 - 1990 Honda NT 650 Hawk GT (NT650K / NT650L): R157 Italian Red
*Note: While 1990 models are mechanically identical to the 1989 revision, they are highly sought after by collectors as they represent the final year of the early engine casting configuration before internal oil passages were overhauled.*
Generation 3: The Internal Oil Castings (1991 - 1992)
The final evolution of the RC31 focused on internal engine cleanup and production standardization across Honda's broader V-twin family architectures.The most dramatic structural revision occurred hidden within the crankcases. Engineers completely eliminated the external braided oil feed lines running up the cylinders, choosing instead to reroute the lubrication channels internally through the engine case castings. This required an entirely unique engine block casting, a revised oil pump assembly, and altered high-pressure lines—meaning 1991–1992 powerplants share very little oil-system interchangeability with the 1988–1990 blocks. To further battle highway wind fatigue, late-model export versions occasionally featured subtle accessory changes, though the core aesthetic remained untouched.
The final generation of the European NTV 650 is instantly recognizable by its exhaust system, which was now a full-length, traditional elongated exhaust muffler that extended past the rear axle to meet stricter noise restrictions.
1991 Honda NT 400 Bros (NT400L / NT400L II): NH1 Black & R107 Bourgogne Red
1991 Honda NT 650 Bros (NT650L / NT650L II): NH1 Black & R107 Bourgogne Red
1991 Honda NT 650 Hawk GT (NT650M): R157 Italian Red
1991 - 1992 Honda NTV 650 (NTV650M): PB161 Wave Blue, NH119 Tempest Gray, NH193 Crystal White, R107 Bourgogne Red & RP131 Moonrise Maroon
1993 - 1994 Honda NTV 650 (NTV650P): G130 Toscana Green, NH1 Black & R110 Monza Red
Final production runs of the Bros & Hawk GT concluded in late 1992 as Honda retired the expensive twin-spar aluminum frame. But the Revere was kept in production until 1997, where it was succeeded by the NT650V Deauville, which eventually evolved into the NT700V touring bike, and finally the NT1100 Sport-touring version of the Africa Twin (which I've been super interested in and may even write about!)
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