Triumph Daytona 955i / Speed Triple 955 Service Manual (2002-2004)

Triumph substantially revised the Daytona 955i for the 2002 model year, while retaining the distinctive 955 cc three-cylinder layout that had become central to the company's performance motorcycles. The redesigned engine adopted new high-pressure die-cast crankcases, revised internals and a higher 12.0:1 compression ratio. Period testing described the changes as a significant mechanical redesign rather than a simple styling update, while preserving the triple-cylinder character of the previous Daytona.

The factory service manual specifies the Daytona version of the engine at 149 PS at 10,700 rpm and 100 Nm at 8,200 rpm. Triumph combined the engine with a six-speed transmission, sequential electronic fuel injection and chain final drive. The Daytona remained the more highly tuned sports application, with its engine producing substantially more peak horsepower than the Speed Triple even though both motorcycles shared the same 955 cc displacement and basic 79 × 65 mm engine dimensions.

The Speed Triple was also heavily revised for 2002. It received much of the updated Daytona engine technology but in a lower-revving tune intended to emphasise road-going torque and throttle response. The factory manual rates the Speed Triple at 120 PS at 9,100 rpm and 100 Nm at 5,100 rpm. Triumph also revised the chassis and styling for the new generation. Contemporary testing noted reduced weight, a shorter wheelbase and sharper steering geometry, while retaining the naked twin-headlight identity that had become central to the Speed Triple.

The two model lines then diverged. The 955 cc Speed Triple was replaced by the new 1050 cc generation for 2005, while the Daytona 955i remained in Triumph's range until the arrival of the all-new three-cylinder Daytona 675 era. For this combined product, that makes 2002-2004 the cleanest catalog range. It matches the period in which the two motorcycles named on the factory cover were simultaneously part of Triumph's 955 cc generation and avoids implying that the later 1050 Speed Triple is covered.