These were: a sophisticated long travel suspension, a liquid cooled two stroke motor and a fully manual 5 speed transmission for 85 86 models and a 6 speed transmission for the 87 92 models. It was a machine exclusively designed for racing by highly skilled riders. Honda responded a year later with the FourTrax TRX250R a machine that has not been replicated. Kawasaki responded with its Tecate 4 250. In 1987, Yamaha introduced a different type of high performance machine, the Banshee 350, which featured a twin cylinder liquid cooled two stroke motor from the RD350LC street motorcycle. Heavier and more difficult to ride in the dirt than the 250s, the Banshee became a popular machine with sand dune riders thanks to its unique power delivery. The Banshee remains hugely popular, but 2006 was the last year it will be available in the U. S. due to EPA emissions regulations. In Canada, however, the Banshee will be back for the 2007 model year, still featuring the same parallel twin, 350cc, two stroke engine that made the machine famous. Safety issues with 3 wheel ATVs caused all manufacturers to switch to 4 wheeled models in the late '80s, and 3 wheel models ended production in 1987, due to consent decrees between the major manufacturers and the Consumer Product Safety Commission the result of legal battles over safety issues among consumer groups, the manufacturers and CPSC.