The Ducati 998
, a successor to the Ducati 996
and the final variation on the Ducati 916
, was produced in various models from 2002 to 2004. The new Testastretta
engine shared many similarities with the previous Desmoquattro engine in the 996, although it was completely new from the crankshaft
up. Testastretta means narrow head and refers to a complete redesign of the cylinder heads
. The desmodromic
valve actuation method was retained.
The 996 had a bore and stroke of 98.0 x 66.0 mm. The bore and stoke of the 998 was more oversquare at 100.0 x 63.5 mm. The included valve angle was reduced from 40 degrees on the 996 to 25 degrees on the 998. Valve sizes were increased, and the camshafts had slightly increased lift, but with shorter duration.
The 998R and non US 998S models had different crankcases with a deep oil sump. The standard 998 had crankcases which were very similar to the previous Desmoquattro. The non US 998S as well as the 998R had revised cam profiles which provided more power than the standard 998. The 998R model used a 104 x 58.8 mm bore and stroke which actually displaced 999cc, and was very similar to the engine used in the subsequent 999R model.
In 2001, Ducati introduced the 996R (see Ducati 996
) with the 998 cc Testastretta engine. This bike was the true introduction of the Testastretta engine and the 998 model. The engine was similar to the 2002 non US 998S. Only 500 were sold... Read More