Yamaha FZ750

Up until 1978’s big splash XS-Eleven, Yamaha’s most prolific four-stroke was the parallel twin XS650. Rather ironic for a company that was enjoying overwhelming success in top-level motocross and GP racing. Well known for producing giant-killer two-stroke twins before the eventual ban, Yamaha was behind a vast import market, but there was no open class four-stroke on the docket to compete with Kawasaki’s 900 Zed or Honda 750. Debuting with a smash, what happened in Yamaha’s immediate future saw the big Eleven solidly trailing the pack before its debut year ended in 1978, followed up by a range of sporting Seca models. While notable, the 600-through-900 fours weren’t sales busters, yet each provided critical info used to build better. Defining what company insiders called ‘Yamaha handling’ was the brilliant FZ400 – a machine so utterly capable it’s still competitive on a modern scale. Clearly awakened from its nap, three straight Yamaha stunners were released in succession to earn wide acclaim. 1984’s FJ 1100 was still big news when the V-Max arrived, but the spotlights moved when the Pure Sports FZ750 took center stage.

Despite strong Euro leanings, I’m not without some experience. My two oldest brothers purchased matching 750cc triples in 1978, a period when Yamaha was unsuccessfully casting its marketing net into Honda’s waters with inline shafties and metric cruisers. Personally, I’d stopped paying attention to the Japanese right about the time Yamaha began making serious inroads in road burner tech, but they were not alone. Picking up the study later showed Yamaha’s mid-80s burst followed a time the firm were floating RD350s and 900cc fours against daunting opposition. Knowing what must be done, the Hamamatsu giant worked methodically. After a long decade of four-stroke study, Yamaha found its stride.

According to Japanese pressman and former GP pilot Ken Nemoto, focus for the FZ 400 (here in red, white and blue) was far different than the FJ 1100 (in silver/red) which despite being tested as a sport/handler was designed for straight line stability at Autobahn speeds. Mixing various pros and cons of the 16” wheel, Nemoto said the FZ met its goal of being a fast, forgiving machine capable of new levels of performance. Not as a racer, but instead to enhance the skills of the average rider. So while the FZ found success in works guise (see Eddie Lawson, 1986 Daytona 200) it still lives in the shadow of Suzuki’s vaunted GSX-R750. “The reason behind the Yamaha Handling reputation was clear” writes Nemoto. “Factory developers stuck to their long-held values and experi. ence, resisting the sway of popular trends during that time.”  Read Nemoto’s full report here.

It isn’t possible to discuss the FZ’s perimeter frame without including the orientation of its engine; both of which contribute in creating the FZ’s in motion character. Canted forward 45-degrees with four 34mm Mikuni downdraft carbs, the engine/chassis concept was developed together. Dyno tested to an astounding 85-hp @11.500 rpm by Cycle in its June of 1985 test, the DOHC, 749cc liquid-cooled Genesis offered the same flexibility as other multi-valve engines, but with added scream due to extra top end volume. The FZ’s new combustion chambers were so efficient (three 21mm intakes and two 23mm exhaust valves) Yamaha could bump compression to a lofty 11.2:1 without detonation. The starter lives inside, next to a five-main bearing forged crank fit with a straight primary gear. More big news included a six-speed transmission and a digital ignition with pick-ups mounted in the crank’s flywheels. No wider than a Honda V4, a fan-cooled 12v generator lives behind the FZ’s cylinder block.

Responsible for the other half of the FZ’s magic, nearly 59” of wheelbase offered the Yamaha rider inherent high speed stability, yet still responsive to input due to a steepish 25.5-degress of rake. Remembered now as a fashion trend, the 16” front wheel allowed precious inches for the forward-canted engine, and this overall geometry provided the FZ rider a slight front-weighted bias most street hotshots find predictable and reassuring. Suspension bit are straightforward save for the chain adjuster on the gas-charged monoshock, but the FZ’s 39mm Kayaba airfork didn’t need the gimmicky anti-dive hardware of the era. Attaching triple disc brakes in a uniform 264mm to six-spoke cast wheels, the rotors are pinched by 2p calipers. And while an aluminum swingarm was de régulier in 1985, the FZ’s rising rate linkage and needle bearing supports were not. “The FZ represents a synergy of chassis geometry” wrote Cycle’s editors. “Like all elegant solutions viewed after the fact, the decision to angle the liquid-cooled cylinders 45-degrees forward is an engineering inspiration so sound, you to wonder why it wasn’t done before.”

In less than a year the FZ lost its spot atop the 750cc mountain to Suzuki’s lightweight GSX-R750. As a fan of the brand and the Gixxer’s special frame approach, I assumed urban legend saying the FZ was simply another brick in Yamaha’s wall correct. Winning the Castrol Six-Hour in both 1985 and 1986 gives pause, as does the head on comparison published by Cycle Guide in April 1986. Sixty-pounds heavier the FZ packed the features left off its more spartan rival, including a full cockpit and main-stand. Ignoring the extra poundage Yamaha’s FZ recorded faster sprints, quicker roll-on times and a top-end nearly equal to the FJ1200. It gave the Suzuki fits on the track. “Despite its stellar specification the GSX-R lacks the FZ’s power, agility and balance” wrote the editors at Cycle Guide. “Naturally, this goes to show that adding up numbers on a spec doesn’t always tell the whole story.”

A benchmark in engineering and application, the approach Yamaha took designing and building the FZ 750 was copied nearly as much the layout itself, but imitation is the sincerest form of flattery. Not currently on the hot list that includes early Z900s, CBXs, or even early editions of the GSX-R, the FZ represents good value for the vintage superbiker. I’ve kept track of online sales and found a surprising lack of available early (1985-6) FZs, many of which were surely used up or broken down. The reliability record is strong due to the engine’s forgiving service schedule and its low stress components. Parts aren’t easy but used bits remain in circulation. A brief survey of current and former owners found a consensus regarding carb synchranation and the importance of using the correct fasteners (to limit plastic cracking) but opinions are all over the map regarding tires. With no real warts, the most common complaint was aimed at the 750’s thinly padded saddle. A pioneer in terms of its proddy perimeter frame and weight bias the Yamaha’s squared, solid good looks still pass the test and the bike’s performance remains more than good enough for the spirited weekender, freeway commute or the occasional track day. An unforgettable experience mixing high revving horsepower with a truly well-controlled chassis, the FZ 750 marks the spot where Yamaha moved ahead of its contemporaries. Nolan Woodbury

 

Yamaha FZ 750 Genesis
Engine
749cc liquid-cooled, DOHC inline four
Inclined 45=degrees, 5v per cylinder
Bore x stroke: 68mm x 51mm
Compression: 11.2:1
Intake: 4-34mm Mikuni CV
Ignition: Electronic pick-up
Gearbox/drive six-speed, geared primary,
Chain final drive
Chassis
Box and round section cradle.
25.5-degree fork angle
Suspensions: 39mm Kayaba air spring
Yamaha monoshock
Brakes: 3-264mm rotors with 2p calipers
Wheels/tires f/r: 120/80/16” – 130/80/18”
Dry weight: 494-lb
Top speed: 145-mph

*Photos: Cycle, Yamaha, MCN

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