Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles
Issue link: https://magazine.cyclenews.com/i/1478157
Yamaha FZ750 to create what he called the MC2, which incorporated his design of front-end using a car-type upright to hold the front wheel and brake calipers, pivot- ing by means of upper and lower suspension arms, or pull-rods. It was actually the steering process, rather than the suspension side, that had puzzled engineers for ages, and Parker's solution was via what he termed a "steering shaft"—in effect a telescopic unit itself—which incorporated special bearings to allow the shaft to move with the sus- pension. Parker had studied the Elf bikes, and particularly why they had not achieved the success he felt was deserved. He felt the problem was "bump steer," whereby during the sus- pension's travel, changes in the angles of the linkages produce unwanted input to the front wheel, and hence, the steering. Parker's "steering shaft," which he patented at considerable expense, was the solution. The original Honda 600-engined de- velopment machine demonstrat- ed Parker's ideas but failed to convince Honda to take up the scheme. Next stop was Yamaha, who showed a little more inter- est, and the prototype was test ridden at Willow Springs Race- way in Southern California by no less a figure than Wayne Rainey, who gave it the thumbs up. This was enough to swing Yamaha to support Parker's project, providing an FZ750 as well as the input of their Califor- nia design studio GKDI, which produced the bodywork for what became the MC2. Late in 1987, that machine appeared at the Milan Show, and a little further down the track, Yamaha entered into an agreement with Parker to access his patents for the production of an all-new sports touring machine, based around the successful FZR1000 power- plant. This was to evolve into the GTS1000, but along the way, the svelte MC2 concept added considerable bulk, and although Parker went to Japan several times to view the progress, he was not permitted to have any engineering input. He said later that he only ever saw the bike fully clothed in its extensive bodywork, and only had the opportunity to measure the front-end after the GTS1000 had reached the produc- tion stage. At that point, he realized that his design had been compromised and that the upper arm of the front suspension was too short, meaning that rake and trail increased with steering angle, producing heavy steering at slow speeds. The GTS1000 duly ap- peared, slightly flawed front- end and all, while Parker moved on, producing a new Suzuki GSX-powered model which further refined his theories. By 1993, the GTS1000 was on sale. The GTS was marketed as incorporating the Yamaha Omega Chassis Concept—Omega cho- sen because the frame as such resembled the Greek letter Ω. Because the loads gener- ated from the front suspension were now transferred (via the swingarm) back to the front of the chassis rather than up to the steering head as on a telescop- ic-fork bike, the frame could be totally redesigned. That frame consisted of horseshoe-shaped cast aluminum sections welded together, plus bolted up lower sections which were remov- able to allow the engine unit to be dropped out. Suspension at both ends was by swingarm—the rear mounted in the conventional way through the main frame be- hind the gearbox and the front, CN III ARCHIVES P132 fully clothed in its extensive opportunity to measure the front-end after the GTS1000 tion stage. At that point, he the upper arm of the front suspension was too short, slow speeds. end and all, while Parker Suzuki GSX-powered model Perhaps we got a little carried away with our headline on that one.