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FZR 1000
Of course, the big news on the 1989 model was the addition of the EXUP (EXhaust Ultimate Powervalve), which is a computer-controlled butterfly valve located in the exhaust's collector. It was first seen on California-only models of the 1988 FZR400 in an attempt to make the high-revving little motor pass the tighter emissions restrictions imposed on all vehicles sold in the state.
At idle and part-throttle, the EXUP closes down, increasing exhaust back-pressure, which effectively re-tunes the pipe for low RPM running and makes the engine more efficient by smoothing out the power pulses. When you're really honking along, the EXUP opens and the engine sees a huge, large-diameter free-flowing exhaust. Power is up throughout the rev range, and emissions are kept to a minimum. Thus, Yamaha technicians were able to develop an engine capable of satisfying two seemingly dichotomous objectives with a single device. While riding, the valve goes unnoticed. That is to say there are no noticeable steps or surges in the powerband -- the rider feels a seamless, constant surge of power that seems to increase exponentially with the engine's revs.
Living with the big Yamaha for the last five years has been a real pleasure. It feels just as at home going to Laguna Seca as it does going through the ultra-fast top-gear Turn Eight at Willow Springs. The riding position works well on fast, sweeping mountain roads, but will soon become a strain on the neck and wrists while droning on the freeway. Fortunately, the big five gallon gas tank provides a comfortable fore-arm perch to ease the pain when the road turns into a yawn.
