Yamaha Xs750-2d
YAMAHA XS750-2D
Cycle World Road Test
A Long-Haul Triple with Power, Comfort and the Nicest Exhaust Note on the Road
Rolling through the nicely banked turn north of Scotchman's Cove onto the flat empty road just waiting to vanish beneath the whiskey tenor of the Triple's exhaust note, cold blue ocean on the left and warm green hills on the right, the Yamaha XS750 works just fine and everything else doesn't mean a damned thing.
The XS750-2D is a great motorcycle. There is a lot of everything else.
Too bad about that. As mentioned elsewhere in this issue, Yamaha is the winner of the 1977 Most Improved Product Line trophy. Yamaha has a complete fleet of new and better bikes, with Multis and Monoshocks everywhere you look. All to the good, no question.
But in the present case, this treasure trove of better products threatens to dazzle the public away from good, solid virtue.
When the 750 Triple appeared last year, it was new and powerful and different. We billed the XS750D as Yamaha’s Flagship, which it was. If it wasn’t as quick as some other 750s. if it didn’t have the largest engine in the marketplace, well, Yamaha was after the more sophisticated buyer. A shaft-drive, touring-oriented Bargain BMW was a logical way to approach this market.
Here we are, though, for the 750 Triple’s second year. The XS750 pictured and tested here is the XS750-2D, or the XS7502D or even the XS75011D. The factory literature uses all three designations. There is some confusion, obviously about just what the 2D, the term we’ll use from here on, is supposed to be.
Never mind competing brands for the moment. The 1976 XS750D was—in the factory’s view—a 1977 model. It was also a sports model with low bars and 3-into-l collector exhaust and relatively firm suspension. Because it was an early 1977, the XS750D continues into calendar year 1977 virtually unchanged.
On the other side of the 2D. in the Yamaha showroom later this model year will be the XS1000. It is the new flagship, and has an inline, transverse DOHC 1000cc Four engine, shaft drive, alloy wheels, three disc brakes and maroon paint. Mercy sakes. The Four has square headlight and turn signals and the 2D Three has round ones. If you don’t know that, you can hardly tell the 2D and the XS1000 apart.
The development guys at Yamaha rub their hands at the prospect of being on an XS1000 and meeting a Kawasaki KZ1000 on an open road. The Yamaha catalog shows a great assortment of touring gear for the XS750D and the XS1000. Fine for those models and for Yamaha sales as a whole.
But. If the original XS750 is a sports bike with touring potential and the XS1000 is a touring bike and asphalt ripper beyond human experience, what is the XS750-2D?
Enters now the motor reviewer’s dilemma. Labels are so easy. Show the motoring press a machine that’s the quickest, fastest, biggest, smallest, cheapest, most practical, in short, show the press a fact on which to hang an oversimplification and we will do it. Don’t have to think at all. And the buyer can sally forth and select the one quality which to him or her means Thing to Have.
Do this to the 2D and it comes out a loser. Unfairly.
That isn’t an acceptable way to review an excellent bike.
Instead, let’s examine the 2D just for itself.
The first impression is one of good looks. Make that stronger. Good taste. The restrained, contrasting elegance of the wheels, black engine, maroon paint and chrome exhaust system drew the attention of motorcycle enthusiasts and the general public. Riding in traffic meant answering questions from drivers. Parked for pictures, the 2D drew crowds. Neither always happens even with an all-new bike and both are evidence of an appeal which must be worth something in terms of pride of ownership.
The idea of a transverse inline Three isn’t new. It is a good idea. Three cylinders allow a narrow engine for its displacement. Concentrating the engine weight in the center gives what engineers call a low polar moment of inertia, which means that a compact mass can change position more quickly than can the same mass using more space. That means the bike will respond well to rider input, which all adds up for more agility than you’d likely get from a 750 Four.
The engine layout otherwise is conventional; double-overhead camshafts; 3into-2 exhaust, which allows low noise and semi-tuned pipes, and a pair of smaller mufflers that provide additional cornering clearance.
What an inline Tripe is, is different. A standard Four has its pistons working in pairs, so when one pair is up, the other pair is down. Each pair balances the other, while at the same time the constant startstop motion means there’s always some vibration.
The Triple, though, has its crankshaft throws and thus the rods and pistons, spaced equally around the crankshaft, 120 deg. apart. No two pistons are ever doing the same thing at the same time. Instead of having the engine run at a constant start/ stop, the Triple fires from end to end, across the bike and left to right, da-dadum, da-da-dum. da-da-dum. Technically, this produces a rocking couple and what it does is give the Three a sound and feel all its own.
From idle to 2000 rpm, the 2D Three feels like of a Four, a heavy shake as if one cylinder has gone away. From 2000 to 3200, the shake becomes a rasp strong enough to turn mirrors and instruments to fuzz. Past 3200 the rasp subsides into a tingle and from 3500 to the 7500-rpm redline, the 2D Triple is smooth as velvet.
Add to this the sound. The 2D has the most pleasing exhaust sound on the market. (Right, habit is hard to break. Figure one superlative only.)
When the Triple hits its stride, the pipes make music, a harsh yet attractive whiskey tenor, not loud or soft. At full power the Three trumpets of controlled power, with pitch but not volume. Difficult to describe, exactly, as a melody always is. The Yamaha Three sounds like no other engine except the Ferrari V-6, which was two inline Threes on a common crankcase.
In the old days, we had the thump of the Single, the bark of the Twin, the rasp of the Three and the boom of the Four. The laws, though, have turned the others into shadows of their former selves. While this is good public relations, still, a HarleyDavidson that whispers and a KZ1000 that’s quieter than a Harley seem lacking, somehow.
Because of that odd number of cylinders, those widely and evenly spaced pulses, the Yamaha Triple has a sporting sound that’s not a loud sound and it’s good to hear. Character, that’s the word we need.
Yamaha deliberately made the Triple a spirited touring and sports machine, and didn’t stress the engine beyond comfort. Wise, seeing as the shaft-drive Triple is a relatively heavy 750 anyway. Even so, the 2D has more power and performance than the test figures show.
Two factors. One is that the shaft drive’s geometry pulls the chassis up while pushing the rear wheel down. Good for traction but not as good at the drags, where spin-> ning a tire off the line shows up at the clocks. The 2D has too much traction at the starting line.
FRONT FORKS
Description: Yamaha XS750-2D Fork, HD315 oil Fork travel, in.: 6.6 Engagement, in.: $.0 Spring rate, lb./in.: 30/35 Compression damping force, lb.: 14 Rebound damping force, lb.: 25 Static seal friction, lb.: 9
Remarks: The basic XS750 fork design is retained, but it incorporates slight reductions in damping and spring rate, while increasing travel by one inch. The result is a more “plush” ride at little or no expense to control. For light touring, these forks work extremely well. More enthusiastic road riders, however, may wish to try heavier fork oii for increased damping.
REAR SHOCKS
uesc,jptfon. Yamaha XS7~~20 Shock, nonrebuljdable Shock travel, In.~ 2.5 Wheel travel, in.~ 4.0 Spring rate, lb./Jn.: 98/130 Comprau,ofl damping force, lb.: 0 Rebo~j damping force, lb.: 70
Remarks: Spring rate, now progressive, has been slightly reduced, as have damping rates. This combination works fairly well for the lightweight rider at moderate speeds, but may be insufficient for faster, heavier riders. At a slight loss to straight-line comfort, controllability may be improved by the addition of a medium-stiffness aftermarket shock, and a progressive spring of rate proportional to rider(s) weight and loading.
Tests performed at Number One Products
YAMAHA XS750-2D
SPECIFICATIONS
$2198
More of a drawback in every day use are the indirect gear ratios.
Most motorcycles, as we say, have a gear for every occasion. The 2D doesn’t. More like too many gears for some occasions and not enough for others.
First gear is numerically right but the spacing between first and second drops the engine out of its powerband, and adds time in the acceleration test. Third, fourth and fifth are close together. Too close, in some ways.
The 2D engine is great, provided it’s running at a comfortable rpm, between 3500 and 7500. In fifth, 3500 works out to normal highway traffic speed, so you wouldn’t want taller gears. Third is just right for around town. Fourth isn’t far enough from fifth to make dropping down for passing too useful, and fourth isn’t far enough from third to be any help in traffic or up slow hills. Fourth gear hasn’t enough> to do, in short, and if the Yamaha engineers ask, we’ll recommend they put the close ratios at the bottom of the box instead of the top.
This is a minor worry. If the gear ratios are any handicap, it’s when they result in quarter-mile times much slower than those for competing 750s. On the road, the 2D is quicker and more competitive than the tests shows.
The test figures do show an improvement from the 1976 test. The first XS750 has one exhaust pipe and a tuning problem. The split system has improved the curve and smoothed it so the 2D is quicker than the D while being a fraction better on the miles per gallon test.
Shaft drive, by now, is almost routine. Aside from that first blink of surprise when the motorcycle rises under power, the shaft and ring-and-pinion aren’t noticed. There is some play in the drive train, calling for a precise throttle hand during shifting and cornering. It’s also nice to forget about things like lubing the chain, adjusting the chain, replacing the chain, cleaning chain lube off your boots and friends. The shaft is expensive to build, but not—surely because we’re in a buyer’s market—to sell. Light motorcycles and off-road motorcycles probably will use chains forever, but for the touring and big machines, shaft drive likely will become more and more popular.
Because the 2D is intended mostly for touring, the suspension has been changed in considerable detail. Yamaha has used the off-road approach, so to speak. Front wheel travel has been increased from 5.5 to 6.6 in. and the spring rate reduced from 42 to 30-35 lb/in. The extra travel gives more space to swallow big jolts, so there can be softer springs and thus less jar on little bumps. Dampening is also less than before and the front end is a fraction higher, giving more trail, half an inch more wheelbase and more stability at high speeds.
The rear wheel also gains travel, half an inch, and the spring is progressive: softer than last year at first, then harder as the shocks near their stops. There is virtually no compression damping and less rebound damping than appeared on the D. This isn't as extreme as it sounds. Because a shaft-drive motorcycle rises under power and chain drive pulls the bike down, a chain-drive machine needs more rebound damping.
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The 2D rides beautifully across all surfaces, fast or slow. Ridden briskly, the 2D becomes, well, not quite a handful, but surely something calling for total concentration. There are no bad habits or scarey moments, but because of the weight and bulk, the 2D does not like being pitched into corners or flipped through a tight righthander, then flopped into full left lock.
The only distressing habit displayed on the test, in fact, was some sort of interplay between the 2D and the Bridgestone tires, leading to over-reaction to rain grooves on the highway. Snaked badly. While that trait never has thrown anybody down, far as we know, it is disquieting.
Two-up tourers might benefit from air adjustable shocks. Beyond that, we wouldn’t change a thing.
Brakes are fine. Better than fine. The two front, one rear disc system is as good as you can buy over the counter and the leverage for hand and foot has been worked out well. This is a heavy bike, but its stopping distances are commendably short while there’s plenty of feel and never an impression either wheel is about to lock.
The high handlebars seemed comfortable at all speeds although wind pressure at 70 mph and above made the upright riding posture tiring. All test riders made favorable comments about the seat, as did the passengers. Also plenty of room back there, they said. And as always Yamaha's self-canceling turn signals won all our hearts, even those who don’t believe we need to be taken care of.
Couple quirks. The 2D has a headlight monitor panel which is supposed to glow when one of the headlight elements burns out. The panel on the test bike glowed whenever the headlight was on. And the mirrors mount with lefthand thread on the right, righthand thread on the left. Why? Or if they must do it. a swap of thread direction would at least mean the wind pressure would tighten the mirrors instead of letting them swing back loosely.
There’s the usual tool kit in a tidy tray beneath the seat and even a separate storage box aft of the battery. Comes with its own lid and it would make a fine place to stow spare plugs, fuel hose, fuses and items of that nature.
Grips drew mixed reviews, with some chaps liking them and some saying the grips are just like all production grips on road bikes, that is, too small, too hard and with lumps and bulges in all the wrong places.
The conclusion sounds faintly like faint praise and it is not supposed to be.
The Yamaha XS750-2D is a rewarding motorcycle. Fast, efficient, attractive, the 2D is completely devoid of temperament. The exhaust note alone is worth the price of admission, the 2D has every improvement and latest feature on the market. It can be ridden as fast as most of us can get away with, in more comfort than you’ll get from the sporting roadsters.
Touring riders who buy to please themselves rather than impress their neighbors will find the 2D an excellent choice. If not many people so choose, the fault is not with the bike. El
