Yamaha's design team have produced an all-new chassis for the second-generation R1 that enhances the qualities of the original machine, and by doing so elevates the machine's handling qualities, and in particular its cornering abilities, to a new level.

The main design goal for the second-generation R1 chassis was that it would offer a linear and direct response in all aspects of handling performance, and this aim has been achieved successfully by creating an all-new frame and swingarm, uprating the suspension and braking systems, reducing overall weight and modifying the riding position.

A key factor in attaining linear handling qualities has been the creation of a new Deltabox III aluminium frame that incorporates the 998cc slant-block engine as a fully stressed member.  The engine has been raised by 20mm within the new Deltabox III frame.

The new machine runs with the same ultra-short 1395mm wheelbase as the previous model, and the new frame offers 30% higher rigidity levels for even more responsive handling performance. Another new feature for 2002 is the fitment of a fully-detachable aluminium sub frame that allows easy access to the rear shock absorber.

At 582mm, the extra-long swingarm retains the dimensions of the 2001 model, but that is where the similarity ends. Featuring a delta-shaped portion on its left side and an arched-shaped section on the right side, the asymmetrical swingarm has been developed to accommodate engine performance-related components such as the new EXUP and titanium muffler without compromising their location or design.

The new swingarm also incorporates a cast aluminium pivot assembly that helps increase overall chassis rigidity for more direct handling characteristics. In order to accommodate the higher engine mounting position the swingarm pivot axis on the new R1 is 17.5mm higher, and the swingarm slant angle is increased to 11.8 degrees for quicker handling response.

The front-suspension assembly is a key area in any high-performance motorcycle, and the design team focused their efforts on improving upon the class-leading system featured on the original R1. Complementing the stiffer frame and swingarm is a new-design inverted front fork assembly that features larger diameter 43mm tubes, 2mm larger than the 2001 model. The larger tubes offer increased rigidity for direct handling characteristics, and by reducing the wall thickness of the tubes from 2mm to 1.75mm, and also by using localised thinning on the outer tubes, these stiffer forks weigh the same as the previous design.

Enhancing cornering potential was one of the main aims of the design team, and for this reason the 2002 model runs with a shorter 120mm fork stroke, 15mm less than previously. Together with the use of higher rate fork springs and an increase in the range and number of adjustment settings, this shorter stroke reduces the potential for front/rear rocking motion during aggressive cornering, and increases potential cornering performance.

As well as running with stiffer front forks, the new R1 features revised front-end geometry. Fork offset has been reduced from 35mm on the 2001 model to 25mm on the new R1, the same dimension as the R7, and trail has been increased from 92mm to 103mm. This new set up makes for a more linear response during turning, while new one-piece hollow forged aluminium handlebars and a lighter steering shaft pipe ensure a more balanced feel.

Changes to both the engine character and frame design have necessitated a review of the rear shock absorber performance, and for 2002 the spring rate is raised and the settings have been changed to suit different riding styles, rider weights and surface conditions. In addition to its improved operability the new shock benefits from a new cold-forged aluminium preload adjustment cam that reduces overall weight.

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