1983 the first sport bike based on the V4 became available:the Honda VFR-750 Interceptor. AMA rules for Superbike racing were changed in 1983 to decrease maximum engine size from 1025cc to 750cc. The Honda Interceptor was ready to compete in this new category. In addition to the innovative V4 engine configuration, it was liquid cooled, and it sported a rectangular tube steel frame, to increase stiffness, as opposed to the more traditional round tubes of the UJM era. The Interceptor was a breakthrough for Honda, and it won many races, including Daytona, and was the second-place finisher in the series. A year later, in 1984 the entire front row at Daytona were Interceptors and Freddie Spencer repeated his win on the V4 Honda. In 1985, both Yamaha and Suzuki answered the challenge with their own innovations. Yamaha offered the FZ750 which was the first in a series of bikes with 5 valves per cylinder. While it was still an inline 4, the cylinders were set at a 45 degree angle, unlike the more typical nearly vertical placement common to UJMs. The frame was rectangular section steel like the Honda. It was into this competitive environment that Suzuki dropped the first 750cc GSX-R model ready to race in the new size mandated by AMA Superbike rules. The GSX-R had the most conventional engine of the three: a four valve per cylinder, inline four - it was a clear descendant of the previous GS series of motors. Cooling was provided by what Suzuki described as an air-oil mix. Oil temps were kept low by a large oil cooler, and engine internals were designed to push the oil at pressure as a spray where it was most needed, notably the underside of the pistons. The principal designer for the bike was Hiroshi Fujiwara, a Suzuki engineer. The frame was the most innovative aspect of the bike. Suzuki abandoned steel altogether and built the frame from welded square section aluminium tubing. To gain the rigidity they wanted, the tubes were quite large, giving the bike a unique appearance. Whereas the Honda and Yamaha were fast street bikes that could be easily raced, the Suzuki was clearly a race bike that could be ridden on the street. The seating position was the racer's crouch, not the street rider's semi-upright one. It shipped stock with the motor tuned to deliver 100HP, but could be easily boosted