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Motorcycle Investor mag

Ducati 851 profile

(by Ian Falloon, June 2022)

Falloon on the fascinating but flawed ground-breaker for Ducati

1988 was the first year for the World Superbike Championship, and with the requirement for 200 machines to be built for homologation, Ducati produced the 851 Superbike Kit and Strada.

Known as the “Tricolore” because of the distinctive red, white, and green colour scheme, 207 Superbike Kits and 304 Stradas were constructed and sold at a premium price. Unfortunately, while they promised much, they were under-developed. The strange equipment typified the idiosyncratic Ducati foibles of that era.

As a homologation special the 851 Superbike Kit was possibly the more flawed of the two 1988 production versions. Although much of the specification was of a high standard, with a claimed 120bhp the engine performance was lacking for racing.

While the Superbike Kit came shod with racing slicks on 17-inch magnesium Marvic wheels and was definitely not street legal, somewhat surprisingly it also had a headlight, taillight, and electric start. Thus it was decidedly overweight despite an optimistic claim of 165kg. The dry weight was more in the region of 189kg, this rising to around 200kg fully wet.

Although obviously too heavy for a real racing machine, the Superbike Kit did at least offer acceptable handling. This couldn’t be said of the more street oriented 851 Strada that came with Marvic/Akront 16-inch wheels and provided unusual steering. These wheels seem to have been left over from the limited edition 750 Montjuich and Santamonica production run and were unsuited to the larger 851.

The 851 Superbike Kit and Strada may have been limited edition models with many individually fabricated pieces but they were a disappointment. The Superbike Kit was neither racer nor roadster and while the Strada provided exceptional performance for a twin the premium price ensured many remained unsold through until 1989.

Still, the 851 Strada undoubtedly raised the stakes for street motorcycle two-cylinder performance. The Italian magazine Moto Sprint has often received the first test machines out of the factory and they achieved a top speed of 238.7km/h with a standing start 400 metres in 11.03 seconds at 197.207km/h.

While the 1988 851 Strada was flawed, fortunately Ducati made amends with the improved 851 Strada of 1989. Although no longer a limited production model (751 were constructed), functionally the 1989 851 was a vastly improved machine over the Tricolore Strada.

Central to the improvement for 1989 were 17-inch wheels front and rear, the rim sizes of 3.50 and 5.50 inches being identical to those on the 851 Superbike Kit those the wheels were aluminium Brembo. These sizes were state-of-the-art for the time and remain so, identical sizes continuing on the current 996.

Also contributing to the superior steering was a reduction in the steering head angle, to 24.5 degrees and less trail at 94mm.

Although the Weber IAW 043 (07) injection system now featured only a single injector per cylinder, the engine still had the Pankl H-section con-rods. With an 11.0:1 compression ratio there was a slight power increase to 105bhp at 9000rpm (at the crankshaft).

Other improvements over the earlier Tricolore included twin 320mm front discs, though these were no longer the fully floating cast-iron type. Setting off the revised 851 Strada was distinctive red paintwork. The 1989 Strada performed similarly to the earlier model, with Moto Sprint managing a top speed of 240.9km/h and a standing start 400 metre time of 11.11 seconds at 194.877km/h.