HONDA The Power of Dreams

Development of the NV0B began in mid-October 1984, and the machine was completed in mid-February 1985. The technology cultivated in HRC's previous road racers was diverted to components such as the front and rear suspension, wheels, and brakes to build it in just four months. However, improvements and adaptations were, of course, made.

For instance, the NV0A had a bottom link rear suspension, but the NV0B had no additional space under the engine where the four exhaust chambers were to be placed, so they relocated the link system on the upper side of the swingarm base. They had used this design on the 1982 NS500 [NS2A], but there was a tendency for the two tension rods on the NS2A to be twisted, which made it difficult to operate. Therefore, they made the cross-section of the rod on the NV0B H-shaped, and instead of two rods, it was made V-shaped and integrated to increase rigidity. Also, as there was no space to place the separate reservoir tank away from the damper body like the NV0A, a new type of rear shock with the reservoir attached to the main body was developed and used.

The NV0B's most challenging aspect was dealing with the four expansion chambers. Unlike the NV0A, a layout that passed over the engine was decided not to be used.

The chassis designer, Kaoru Yamamoto, said, "We made rough layouts at our desk, such as two above and two below, or two crossed in front of the cylinders. However, each had positive and negative aspects, and we finally settled on a layout with four chambers passing under the engine."

The story continues when they decide on the layout. In the case of a multi-cylinder two-stroke engine, the principle is that the specifications of the divergent section, straight section, and convergent section must be the same for each chamber. However, the NV0B engine is a V-type four-cylinder with all cylinders exhausting from the front, and the positions of the exhaust ports for the two cylinders in the front bank and the two cylinders in the rear bank are entirely different. Yet, all four chambers had to fit into the space under the engine while maintaining the exact specifications. It was a minimal space, and the goal was to secure a bike's lean angle over 60 degrees at the time.

Yamamoto and his team used their homemade tools and ingenuity to create four chambers with identical specifications intertwined like a puzzle ring. They completed the development in a short period of four months. The NV0B that was born in this way became a machine that demonstrated historic strength, winning seven of eleven World Grand Prix races with a winning rate of over 60%.