Triumph Press Information
The brakes were uprated from the original brief as soon as the decision was made to use the 955cc engine instead of the 885cc unit, and are the same as the acclaimed items on the 955i. The need for the Sprint ST to be less intimidating than a pure sports bike could have been compromised by the 955i’s fiercely powerful brakes, but because it is slightly heavier the effect has been to reduce some of the brakes’ sharpness without dampening their feedback, leaving them perfect for the application.
STYLING
Work on the styling of the Sprint ST started at the very beginning of the project when independent designer John Mockett was brought in and briefed on the basic aspirations of the machine. Mockett’s particular strength for Triumph is his awareness and involvement of the engineering issues in design, which makes the factory’s job that much easier.
Triumph and John Mockett tend to start the styling work on a new project with full sized models from the beginning, and the Sprint ST was no exception. Once the first model was built it then underwent an intensive programme of refinement according to its aerodynamic behaviour, ergonomics and of course its looks.
The result is a bike which is pitched at the more sophisticated customer who shies away from garish graphics and multiple colour schemes in favour of a more restrained and classy look rhe form is important but so is the function, which isn’t compromised by gimmicky features.
TESTING AND DESIGN PROCEDURES
A few months after the initial concept and feasibility studies were realised for the Sprint ST, the full design team was assembled consisting of eight staff, each working solely on the new Sprint. This is in line with Triumph’s policy of splitting its staff into teams according to the project they are working on, as opposed to the more traditional practice of dividing people into groups dealing with engine, frame, bodywork and so on. This helps instil genuine enthusiasm from the team for a new bike, which becomes ‘their’ machine.
Because the Sprint ST’s engine is a development of an existing unit (and Triumph already has some experience of lower horsepower versions of the 955i unit for some markets) most of the time allocated to the engine was spent on refining the fuel injection. This was a combination of bench testing and feedback from Triumph’s development riders.
The frame development followed two paths. The new twin spar frame was originally constructed as a model to check it for style, then its dimensions were digitised on a computer using a touch-probe, which can record the position of its tip in three dimensions at the press of a button. An engineering Computer Aided Design (CAD) model was then generated to assess the strength and stiffness of the digital frame using Finite Element Analysis, a computer method which treats the frame as if it was a collection of tiny individual pieces connected together. All of this information allowed Triumph’s engineers to optimise the strength of various areas of the frame and also keep cost and weight to a minimum.
Meanwhile, the geometry of the new frame was assessed by altering a 955i frame to the Sprint ST’s wheelbase, rake and trail figures and riding it on test tracks and on set test routes on public roads. Race track testing was carried out later in the Sprint’s development programme, to ensure that the limits of possible use were considered.
There are distinct stages in the life of a bike leading up to the first model off the production line. The main Development Build machines (the ST1 Build) are used to finalise the chassis geometry and stiffness, the engine development, the structural integrity and rider assessments.