Cycle News - Archive Issues - 1980's

· I • \. YAMAUAs 1985 STREETBIKES: MONSTER-BIKE TOTUE fORE By John Ulrich Yamaha's 1985 streetbike lineup has been unveiled to' dealers and the press, and the shocker of the lineup is the water-cooled, shaft-drive, 135-horsepower, 1198cc V-Max hot rod, essentially a strippeddown, hopped-up Venture. The new bike, styled as a sort of semi-cruiser, sports the largest 18 rear tire - a 150/90-15 - we've seen on a production motorcycle. The look, as Yamaha's marketing department sees it, is that of a hot rod; from the thick, massive rear section to the highlighted carbs, intake manifolds, cylinders and exhausts emphasizing the V engine configuration, to the fake induction scoops mounted on each side of what appears to be the gas tank (more on that later). This motorcycle originated in the United States, in the same marketing department responsible for the rapid proliferation of semi-chopper cruiser and custom styling in the United States; it wa~ built in Japan to U.S. specs. Yamaha engineers expect that the V-Max will be fasterthan the FJlloo; it certainly makes mo~~ power. In the I \ For show or go: (ebow) the chrome-pleted Virego 1000 with Herleyesque styling; (below) the FZ760, which doesn't ~ Celifomie eminions. transition from the 75OO-rpm-redline touring Venture - which is rated at 90 horsepower - to the 95OO-rpmredJine, fire-breathing V-Max, the big DOHC, four-values-per-cylinder, plain-bearing crankshaft Yamaha Vfour racked up a long list of performance and high-output-reliabilityboosting modifications. To start with, the V-Max engine has larger valves with smaller stems; the intake valves measure 30.5mm (up from 29mm) and the exhaust valves measure 25mm (up from 24mm), with 5.5mm stems (vs. 6.5mm stems) to reduce air-flow obstruction in the ports. The larger valves are opened by camshafts with longer duration and higher lift than Venture cams, and closed by stronger valve springs. The pistons and wrist pins are lighter, the crankshaft and connecting rods made stronger by a new hardening and heat-treating process. The V-Max has four 35mm down- • Two views of the V-Mex monsterbike, in the flesh (ebove) end cut_ey (below). EIther wey, it's big end brewnY. Air scoops e,en't functionel. . draft Mikuni carburetors (vs. the Venture's 34mm carbs), and the two carbs on each side' of the engine are linked by a tube filled with a servocontrolled bUllerfly valve. At about 6000 rpm the bUllerflyvalves begin to open; at about 8000 rpm they're fully open,.allowing each cylinder to draw fuel from two carbs instead of one the result is increased power at higher rpm, and Yamaha test riders who have ridden the V-Max with the system disconnected and connected say the difference is remarkable. Yamaha calls it V-Boost. The V-Max has a five-speed transmission and is geared, the engineers say, for the quarter:mile. Styling is as much a part of this bike as is horsepower. The sidecovers are aluminum alloy stampings. The gas tank is located underneath the seat, and reached by pivoting forward the humped portion of the rider's seat. That seat is low, 30 inches off the pavement, and the motorcycle is long, with a 62.6-inch wheelba . Rake is 290, trail 4.69 inches. It's also heavy; how heavy,. Yamaha isn't saying. We'd guess about 650 Ibs. Fuel tank capacity is 4.0 gallons. Mounted under what would be the gas tank if the fuel wasn't actually underneath the seat is a large air cleaner; the console covering the air cleaner carries a small tach and a coolant temperature gauge. The only handlebar-mounted gauge is a speedometer in a chromed housing. The rear wheel is cast aluminum alloy with wide spokes - the spokes are so wide the wheel almost appears solid; those spokes are polished on one side and painted black on the other. The rim size is 3.50-15, carrying that giant 150/90-15 tire. The front rim is more conventionallystyled, a 2.15-18 carrying a 110/90-18 tire. I The V-Max /:omes with triple disc brakes, two II-inch laminated, ventilated discs up front, a third on the rear wheel. The froilt fork has 40mm stanchion tubes and is air-assisted, with a balance tube; a forged aluminum fork brace bolts between the sliders. The rear suspension is conventional dual-shock swingarm, with no shock adjustments except spring preload. The shock springs themselves are tapered, the diameter of the coil being greater at the top than at the bollom to suit the styling. Meanwhile, the single-rear-shock Venture Royale touring V-four returns; the stripped Venture model is discontinued. The Royale comes standard with stereo tape deck; a computerized, automatic-leveling air suspension system with on-board compressor; a cruise-control; 40% more luggage capacity than in 1984; and a 40mm taller windscreen. The travel trunk is moved farther back to increase room for the passenger, and there are four removable soft Iuggage pieces - two fitting inside fairing pockets, two inside the travel trunk. The travel trunk itself has a new latch system so it can be opened without a key - just like a suitcase - or be key-secured. The next-biggest machine in Yamaha's lineup is the 1097cc FJlloo introduced to rave reviews for 1984. The big sport bike has refinements rather than big changes for 1985, including new fuel gauge calibration to more accurately indicate the level of fuel in the gas tank, a seat covered in less-slippery vinyl, new shift-drum ramps for easier shifting, a rubbermounted lower engine cowling to eliminate cracking, new passenger pegs material to reduce vibration transmitted to the passenger, and a 0.5mm increase in piston wrist pin offset - to a fulll.Omm - to reduce piston noise during idling.

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