Using a previous-generation superbike engine in a naked bike has been a common practice to create high-performance roadsters. Honda’s original CB900F Hornet utilized the 919cc FireBlade engine in the early 2000s. However, with modern emissions regulations becoming stricter, the process is no longer as straightforward.
Honda made significant advancements with the ‘SC77’ model in 2017, increasing peak power from 168bhp to 189bhp while meeting the Euro4 emissions limits. Although this power output may seem lower compared to some competitors, Honda’s conservative approach to engine design has made it well-suited for the new CB1000 Hornet.
The transition from Euro4 to Euro5 and now Euro5+ has brought about more stringent emissions requirements. The Euro5+ regulations focus on ensuring that engines maintain their emissions performance over a longer period, rather than simply lowering the limits further. This means that motorcycles must be able to meet emission standards for 35,000km, not just when they are new.
The SC77 engine, with a 76mm bore and 55.1mm stroke, was considered conservative even at its introduction. The Hornet’s engine, based on the SC77, features smaller throttle bodies, reduced valve lift, revised timing, and a lower compression ratio to enhance midrange torque and meet emissions standards. These adjustments result in peak power at 11,000rpm and max torque at 9000rpm, making the bike more usable for street riding.
By repurposing an older FireBlade engine for the new Hornet, Honda has been able to reduce research and development costs, ultimately offering customers a more affordable price tag. The Hornet may have slightly lower power and torque figures compared to the Fireblade, but it still competes well in its class.
Overall, the evolution of Honda’s Fireblade engine in the CB1000 Hornet showcases the brand’s ability to adapt to changing regulations while maintaining performance and reliability. The blend of power, efficiency, and cost-effectiveness makes the Hornet a compelling option for riders looking for a high-performance naked bike. With Honda’s commitment to innovation and sustainability, the future looks promising for the evolution of their motorcycle lineup.
