| Designer | Massimo Tamburini | ||
| Production period | 1976 – 1977 | Production numbers | 15 |
| Power | 39 KW (53 PS) 47 KW (64 PS) | Displacement | 249 cc 349 cc |
| Topspeed | acc. to ratio | Weight | dry 95 kg |
| Price | ca. 3.500 DM (1977) | ||
| Technical basis | Yamaha TZ 250 / 350 |
For the 1976 season, Bimota introduced a new chassis for the Yamaha TZ 250 and TZ 350 engines. Massimo Tamburini built upon the concept of the YB1, once again using a closed double-loop frame with a welded rear section. However, he completely redesigned the connection between the frame tubes and the steering head. The upper and lower tubes crossed in front of the steering head, and the cross tubes used for reinforcement between the upper and lower tubes, as seen on the YB1, were also present.
A major innovation was the rear suspension. Instead of a box-section swingarm with two shock absorbers, Tamburini designed a new tubular cantilever swingarm and an almost horizontally mounted De Carbon central shock absorber, which was attached to the frame above the engine. From this point, an additional reinforcing tube extended to the steering head. Another new feature was the eccentrically mounted swingarm pivot, which allowed adjustments to the chassis geometry.
Bimota also offered the same frame that year for the Aermacchi-Harley-Davidson Grand Prix engines, but with a box-section swingarm and two separate shock absorbers. During the 1976 season, both the YB2 and HDB2 models achieved numerous victories. Walter Villa won five Grand Prix races in the 250cc class with the HDB2 and became world champion. Italian riders Uncini and Buscherini also secured GP wins with the YB2 in both the 250cc and 350cc classes, along with many other podium finishes by various riders.
However, this was not the full extent of Bimota’s success in 1976. Another team competing with a Bimota chassis was Morbidelli. In the first 250cc Grand Prix in Misano, Pileri won with the Morbidelli-Bimota, ahead of Uncini on the Yamaha-Bimota and Walter Villa, who finished third on the Harley-Davidson-Bimota.
A similar success followed in the second 250cc race in Misano. This time, Uncini won on the Yamaha-Bimota, with Agostini taking second place on the Morbidelli-Bimota, and Walter Villa once again finishing third on the Harley-Davidson-Bimota.