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izes the distance from plug electrode to piston crown for superior £lame propagation. Higher lift figures would have caused piston interference and forced lower compression ratios. The combustion process is completed very quickly, greatly reducing power waste through heat loss. And the slight concavity of the piston crown means combustion energy is not wasted in heating a large piston crown surface area. Yamaha experimented with perfectly flat piston crowns, but the compression ratio could not be raised above 9: I with this design. Since the FZ750 builds rpro so quickly, the ignition is equipped with a rev-limiter that prevents the engine from exceeding 11,800 rpm. The forged, one-piece crankshaft runs in five bearings and the transmission has six close-ratio speeds. The closer distance between driveshaft and drivenshaft significantly reduces engine length. The distance between crank center and drives haft center is only 5.5 inches, and the distance between driveshaft center and drivenshaft is only 2.6 inches. This compares with 6.1 inches and 3.3 inches, respectively fpr the X]750. Oil and water pumps are driven off the same shaft and the remote-driven generator is rear-mounted. The hydraulicclutch is wet and uses eight£riction plates and six springs. Great effort was made to reduce mechanical foss within the engine. Pumping loss due to crankcase charging was reduced by using large pressure equalizing holes in the crankcases and between each individual cylinder's crankcase. . Similar pains were taken to reduce friction losses. In addition to the extremely light valve train, baf£les prevent oil in the wet sump from slowing the crankshaft at high rpm, and no oil seals are used at the ends of the crank. Instead, caps with o-rings seal the crankcase ends. Compared with the engine, FZ750 chassis and running gear might seem conventional. Nevertheless, both reflect Yamaha's extensive roadracing background. Like the RD500LC, the wide cradle mai n frame is constructed of box-section steel tubing of high tensile strength. Unlike the RD, the rear shock i mounted behind rather than below the engine. The upper rails follow as straight a path as possible between the steering hcadand swingarm pivot. From downtubes detach foC engine removal, and the top end is casil y accessi ble through the wide-spaced tubes. This rigid layout is further strengthened by the rigid-mounted engine. . A rising-rate Monocross suspension with DeCarbon-type single shock controls the large, box-section alloy swingarm. Pivoting on needle bearings, it is wide enough to accommodate racing tires and the chain line is positioned 4.1 inches from the machine's centerline with this in mind. The new, cast allov wheel comes stock with a wide-profi Ie, 130/80-18 tubeless V-rated tire. The air-assisted front forks feature 39mm tubes, forged-aluminum lower triple clamp bracket, aluminum fork brace, and tapered roller bearings in the steering head. Tube wall thickness is 3mm. The front forks feature a variable, rising-rate damping system that is very light, simple and efficient. Using this inside the fork sliders increases compression damping under rapid compression (the built-in relief valves reduce compression damping w'hen riding over bumps). At less than racing speeds, however, the forks perform like conventional telescopic units. •. Distance between shafts in FZ750 engine is shorter than in an XJ750 engine; the engine is compact. SUPERBIKE LOOKS. SOUND. PERFORMANCE. Two sticks of dynamite with a one-inch fuse. SuperTrapp tuneable slip-on silencers. Twin reverse-cone megaphones tipped with repackable lightweight aluminum silence;s. Slides onto stock headpipes in minutes. No rejetting required. Available now for Kawasaki Ninja. -Soon for 'all Honda Interceptors and new 1985 heavy artillery. Light the fuse and blow the side covers off your competition. $199.95 SUPERTRAPP. GUARANTEED SMOKE. Positioning cam bearing caps over the lobes makes the FZ750 cylinder head 3.0 inches narrower. " lU"" FZ750 ignition triggers are built into outboard flywheels. with sensors in the cases. RG 500 Gamma GSX750R The three ventilated brake discs are stopped by semi-metallic pads mounted in opposed-piston calipers. The thin, single-core aluminum radiator is si milar to that on the RD500LC. Light and compact, its cooling fan is driven by a light, flat electric motor. Finally, a frame-mounted half-fairing protects the rider while dramatically improving maximum speed and and high-speed stability - the drag coefficient is ollly 0.34. The fullwidth l2V rectangular headl i"ht uses a 60/55W ha-Iogen bulb. Constructed o( tough ABS plastic with polycarbonate screen, the fairing neatly houses the meters and gauges on an inner panel dominated by the central tachometer. Left and right fairing sides have ducts to draw out heated air through the radiator and direct it away (rom the rider. They are easily detachable for maintenanc~ • e UmiUd au.ntitie. LMte102 H.P. e 3BB Lbo. Dry e Aluminum F.._ e e 95 H.P. e e Aluminum F.._ OilCool..teOptiONlI130H.P. R_Kit 366 Lbo. Dry eliquid Cool..t e Sq..... Fou< Rotary V_ E"lline FOREST LAWN CYCLE 4710 17th Avenue S.E.• Calgary. Alberta. Canada T2V OV1 (403) 273-2527 c.ontact Tony or John. Dealer Inquiries Invited :'Canada Number One Suzuki Dealer 1983-84" 's MICHELINHI-SP'ORT NOW'NSTOCK 120170 V 16 TF-1 1 100/S0V1STF-11 160/60 V 17 TG-22 130170 V 1 B TG-22 160/60 V 1B TG-22 D.G.T. Approved St....tLec.. Hlp P....orm.ne. Treck Grip UNBEATABLE CALL NOW 800-628-4040 }J6"~~ , .81