Cycle News - Archive Issues - 1970's

co STA N " '" '" 0- N .... Cl INGA EW .ri " u. ;g W Z W ..J U ~ U Angeles Forest is a nice place to ride - and a nice place to stop ridlnq , By Ron Schneiders Just a bit over a year ago I road tested the Yamaha XS-I B. Everything that cou ld possib Iy be wrong, was. The machine preparation was poor and seve ral trips back to the distributor were necessary to ge t things straightened o ut. The machine had some serious design flaws. And finally it scattered and al most scramb led me in the process. My report, naturally, was scathingly critical. So when the publisher asked if I would road test the new model, I said I doubted if Yamaha would even sell me a bike, let alone give me one to test. And thereupon I received my first surprise. They not only gave me a brand new XS -2 but they seemed genuinely happy to have me test it . Whatever else you might say, they've sure got faith in the product. Their faith, however, was not my faith . Motorcycling is a casebook of engineering gimmicks that should have worked but don't and it seems lik e I've bought most of them. No more. Now I wait to see how (or il) it works on the road or trail. For those who tuned in late, the Yamaha XS -2 is a four-st roke vertical twin-powered road bik e. Borrowing a bit of WW-11 terminology, we might call it a m ed ium -range to urer. A nu mber of wri ters have compared the XS-2 to the British tw in s of the same disp lacement, a nd in ferred (or stated) th at the Yamaha is a copy. It 's not so, no more th a n Sophia Loren is a c op y of Elizabeth Taylor. Dimensionally they might be similar, but in terms of personality they're miles apart. When I began this test 1 had one sma ll problem . Normally w hen testing a road bike I like to put a good 1000 miles on it. I feel that's a b o u t the mileage required to have any real faults show up. But in this case there simply wasn't enough time available to accomplish that goal. In fact, aside from some errand-type riding. I had exactly one day on the Yamaha. Here's how it went and what I discovered : Early o n a Friday morning I pulled the bike out of the garage and was These are the headlight and dimmer switches . "Thev are dangerously close together:' says the author . ! f' New this year is a compression release which operates in conjunction with a starting motor. immediately conscious of its weight. Later I found that it weighed 460 with abo u t one gallon of gas in the tank. It was quite chilly, in the high 40s . One of the in t eresting new features of the Yamaha is its electric starter. A small lever on the handlebar not only switches on the starter but also operates a compression release. Once the engine ,h as warmed up, the system works beautifully but when it 's cold it often takes so long to get started that there is danger of ru nning the battery down. 1 found it best to turn the engine about 10 times with the starter motor and then ki ck it once o r twice. Relieved of its starter motor duties, the battery ca n provide a hotter spark and the engine starts right up. Once started, the engine must be warmed up for several minutes and there is n o short-cutting this chore. Soon we (me and Yamaha) were headed up the cold Angeles Crest Hig hway. The bike runs beautifully. A ltitude doesn 't affect it in any d iscernible fashio n. The bike has a new front brake, a powerful disc type. I decided to give it a good lest right at the start by braking hard from 70 mph to about 20 mph t en tim es in succession. There's virtually no fade and more important, there's no tenden cy to twist and dive right. This was one of the big problems with the first bike that 1 tested, and it's apparently been well cured. But I had to stop that nonsence because a few patches of ice and sand were starting to appear. When the traction starts getting nea r zero , you want a very smooth, very even throttle response with just enough power to keep everything in the drive train taut, but not one iota mo re. The smallest jerk or surge of power will break the delicate bond between th e rear wheel and the iced pavement. We h it ma n y ice patches and had n o tro uble, a big plus for the Yamaha. Normally this nice, even response is a . functio n of t he flywheel weight , but the Yamaha's flywheels are rather small and the smoothness can be attributed to fine carburetio n . Coming off the mountain we p layed road race r for a while on the curvy road leading towa rd the desert. The bike behaved very well until I started really pushing. It protested by draggi ng its pegs and stands , by keeping its head down a bit too [ong when I would brake hard for a tum and then falling off-line as it comes up well in the tum . Okay, I'm convinced. But in fact, the bike could be m ad e to hand le quite we ll without m uc h change. The steering is neutral a nd the geometry isn 't bad at all . Mostly it needs stiffening in front forks a nd more clearance, which could be obtained by removing the stands and cu tt ing off a b it of the pegs. There is one p roblem that might be more diffic ult: the frame isn't very rigid. If you're go ing t hro ug h a downh ill S-tum and brake j ust at the m o m e n t when th e bike comes up righ t , you'll find that the b ike feels like it wants to tie itself in a kno t. T his is not a serious problem because the bike is not intended t o be used as a road racer, and most other production bikes are about the same as the Yamaha in this resp ect. The gearbox has a good, positive feel to it and offered no cause for complaint. The ratios are close, making it easy to keep the engine operating in its proper rpm range (4500 to 7000) between 20 a nd 100 mph. From 5 to 20 mph the engine operates in that very comfortable just-over-idle mode that I spoke of earlier. Very smooth. T he bike is heavy t h o ugh , and the e ngine doesn't produce m u ch power at lo w rpm, so to get off th e lin e re q uires a bit of b uzzing and clutch slipping. It's irrita ting at

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