Motorcycles: An engineers dream machine

Over the years, Design News has asked readers to review a current-year vehicle they were about to purchase. They jumped at the invitation, reviewing everything from sedans and sports cars to sport-utility vehicles and pickups.We never considered asking them to review the venerable motorcycle, thinking the response would be meager. Little did we know what a love affair engineers have with their bikes. Perhaps we were too naive. After all, the prestigious Solomon R. Guggenheim Museum in New York held a "sold out" exhibition this year entitled "The Art of the Motorcycle."

So we bit the bullet and asked readers planning to buy 1998-model-year motorcycles if they would be willing to review their purchases. We were inundated with responses. What follows are three accounts of engineers and their dream bikes.

Yamaha YZF-R1: Near-superbike status

I eagerly awaited rider reviews of Yamaha's YZF-R1 after seeing pictures of it at the Milan Motorcycle Show in the fall of 1997. The Holy Grail for sportbike riders has been superbike performance in a roadable machine. The new YZF seemed to be that bike.

So, when the April issue of Motorcyclist arrived in March, I read the article faster than Evelyn Wood. I knew then that I had to find a YZF for myself. I had already been to the local Yamaha shop. They said they had been sold out of their allotment since the bike's introduction in October. After calling all the dealers in Texas, Louisiana, and Oklahoma, I found out just how rare the bike was. Some waiting lists were 20-people long. I finally found a lone bike in New Mexico, so I put my deposit down on March 5, with an expected delivery date at the end of the month.

In the interim, I read every magazine article that came out on the R1. All touted its light weight, high horsepower, and rock-stable handling. I also became a regular visitor of several websites, trying to quench my thirst for knowledge. I even called the dealer every other day trying to find out when THE machine would come in. It finally arrived at my door on April 13.

When the back door of the moving van opened, I saw the meanest looking bike ever. Everyone said the pictures didn't do the bike justice. They were right.

Light weight was definitely a design goal for this bike. With its exceptionally small stature and narrow profile, it's hard to believe that this is a 1000-cc motorcycle. It has a windscreen that appears to be way too small to provide any wind protection. The engine was redesigned to stack the clutch and transmission over the countershaft, resulting in an engine that is 27 lbs lighter than last year. And the fairing is half the thickness of other sportbikes.

Obviously influenced by the Ducati 916, the front snout looks like a hornet ready to put the sting on the competition. Wheel axle bolts and caliper attachment bolts are hollow, decreasing unsprung weight. Every component looks like it went through a government weight-reduction study.

How does it perform? OUTSTANDINGLY! Yamaha claims the bike has a 390-lb dry weight and delivers 150 hp. Wet weight is 448 lb; actual dynamometer results vary from 128 to 132 bhp at the rear wheel. Needless to say, the high power coupled with a 54.9-inch wheelbase results in a bike that loves to wheelie. (The R1 will accelerate from 0 to 60 mph in about 2.8 sec and top out at about 172 mph.)

Handling is extremely stable due to several major changes over last year's model. The long swingarm lets the rider increase power earlier during corner exit. The swingarm also reduces the effect of chain pull--which adversely affects handling--caused by angular changes of the swingarm due to the increased length. The low rake and trail figures combined with a reduced triple clamp offset allows razor-sharp handling. Some riders have experienced handlebar wobble at high speed and, as a result, have installed steering dampers. However, my bike hasn't demonstrated that tendency, even at 150 mph plus.

Slowing down. So the bike will go ballistic, but how does it stop? The R1's brakes are exceptional. The dual-piston calipers allow extremely quick stops with virtually no fade. The combination of high horsepower, precise handling, and great brakes results in a bike that could only have been a vision a couple of years ago.

The leaned-over style of modern sportbikes generally results in forearm, wrist, and lower-back fatigue in city driving, but is required for good racetrack performance. In city driving, the R1 is no exception. However, at speed, the diminutive windscreen allows the windblast to support the rider, which off-loads the pressure on the forearms and wrists. The pilot seat provides good support and remains comfortable after 200-plus miles of riding.

Maintenance has been performed as required. Cost of the 600-mile service totaled $172.48. It consisted of changing out the break-in oil, synchronizing the carburetors, and adjusting the steering head bearing torque. The bike ran even better after the carb sync, with the idle smoothing out from a slight lope it had before the service. The transmission shifting also improved from a clunky-type shift to a smooth click after the oil change. Nary a problem has cropped up after more than 1,300 miles.

In my opinion, the Yamaha R1 has achieved near-superbike performance in a road-going package. Combined with a fairly reasonable retail price of $10,199, the R1 is the sportbike to have for 1998.

Kent D. Copeland,
Project Manager
Oceaneering Space Systems Inc.
Houston, TX

Buell S1WWhite Lightning: Naked pleasure

The 1998 Buell S1W White Lightning is naked, having only a bikini fairing on the handlebars and just enough bodywork to hold the seat and taillights in place. The motor, a pumped-up version of Harley Davidson's air-cooled 1,230-cc Sportster V-twin engine, develops 102 hp/85.4 bhp and 74.6 ft-lb of torque. The result: acceleration from 0 to 60 mph in 3.2 sec, and the quarter mile in 11.56 sec at 115 mph.

The bike has a top speed of 135 mph and gets 45/53 mpg. So far, in three months of driving and with 3,200 miles on the odometer, I have averaged under 50 mpg only once. Moreover, the cycle has never leaked a drop of oil, using less than one quart in the first 2,500 miles.

This is one marvelous piece of machinery. It is surprisingly compact. Compared with a Kawasaki EX500, the S1W weighs in at only 50 lb more and has a 1.5-inch shorter wheelbase.

I purchased my bike from a Harley Davidson dealer in Ventura, CA. Going into one of these shops is like a social event and a secret club. You have to learn new words like "bagger," "dresser," and "knucklehead." You also learn to understand that Evolution has nothing to do with Darwin. The well dressed are in leather of all types.

Buying this bike was a real pleasure. I got no "attitude" from the sales people. At my local Honda dealer, they laughed when I wanted a test ride. "The only way you are even going to sit on it is to buy it," they taunted. The Buell/Harley family was different. They sent me an invitation to test-drive a bike. That was in 1996. After that ride it became sort of a moth-and-flame thing. I just kept finding excuses to go to Ventura. Two years later the Buell was mine.

I bought my bike on March 30. By July 1, I had put 3,200 miles on it. The break-in period was anything but fun. Luckily, it was brief. The manual tells you to keep rpm under 2,500 and speed under 55 mph for the first 50 miles. I read that for air-cooled motors this period must be taken seriously. Recall that this bike does 0-60 in 3.2 sec--it is not possible to twist the throttle and look at the speedometer in time to keep within the proscribed guidelines. As a result, you sort of idle around for 50 miles.

After the break-in period you get to rev it up to 3,000 rpm, a limit that must be maintained for another 450 miles. It was during this time that the engine developed a hiccup at 3,000 rpm, spitting back through the air cleaner. Apparently the carburetor was jetted on the lean side at the factory. As a result, I went in a bit early for my 500-mile service. The dealer used this free check to re-jet the carburetor, change the oil, and check the belts.

Some other things about the bike require getting used to. There is an indicator for loss of oil pressure, but no gauge for oil temperature. Since oil is a primary cooling element, this makes me nervous. Other peeves include: no helmet lock, rubber foot-peg covers that can work off while riding, small turn-signal indicators mounted so low on the console that you don't notice them, and mirrors that look like they were designed by Pee Wee Herman.

One thing about Harleys and Buells: to own one is to modify one. In fact, the bike just sort of dares you to make changes. Most notably, the filter canister for the tank vent resides in a location that screams "Take me off!" Mounted right on the frame, it rests against your leg when stopped. I can't tell if it was put there because Buell sort of forgot about it, or if made to be easy to remove.

Rider tuneup. The bike handles great, with the suspension allowing for complete tuning by the rider. The inverted front forks adjust in both compression and rebound, while the rear suspension adjusts for compression, rebound, and pre-load. The rear shock, located outside the frame just under the engine, is mounted to work in extension. Adjustments require not having to remove anything. The frame/suspension system uses the engine as a frame, becoming the lower member between the steering head and the rear swingarm. The rear arm attaches directly to the engine case. This makes for a low-weight, rigid frame system. It also provides a well-controlled transfer of power to the rear wheel.

Rubber bushings isolate the rider from the drive elements. This results in one of the most vibration-free V-twin rides you will find. At 70 mph, I had virtually zero vibration.

You might get some arguments about the low-tech nature of an air-cooled, single-carburetor, push-rod engine in this day of water-cooled, multi-carburetor, four-valve DOHC designs. However, this motor uses hydraulic lifters, which need no adjustment. The single carburetor also eliminates problems with synchronization. This saves big bucks at tuneup time. The $75 charge for a basic service check is about one-third what you would pay for just about any in-line cycle.

Although the roots of this motor go back 95 years, refinements never stop. Even though it pulls 102 hp, it has an optional seven-year warranty that includes gaskets and seals, meaning you'll never have to live with oil leaks. The dry-sump design has added a larger oil pump in '98, which circulates 50% more oil for increased reliability.

On the more esoteric side, I have never ridden anything that sounds so good when you drive it. Stories about V-twin engines are true--they really are a pleasure. All in all, the Buell S1W incorporates reliable technology in innovative ways to achieve a truly high-performance, low-maintenance ride, while being extremely fun to drive.

Bob Setbacken,
VP Engineering
RENCO Encoders Inc.
Santa Barbara, CA

Honda VFR 800 Intercepter: No-remorse riding

Buyer's remorse? I thought I had made the wrong choice selecting a Honda VFR 800 Interceptor as my new bike for the next millennium. But the time was right to replace my 1981 R100/7 BMW, saddle bags and all. So what cured my remorseful mind? As the throttle was twisted, thoughts of other bikes vanished.

What's to like about the new VFR? Just about everything: engine, brakes, chassis, transmission, tires, fairing, and lighting. The all-new-for-'98 VFR is somewhat of a technical showpiece for Honda. The four-cylinder, four-valve-per-cylinder engine has high-pressure-formed ceramic and graphite-impregnated aluminum sleeves and pressure-lubricated pistons. A 3D-mapped injection system, which eliminates more than two pounds of carburetors, supplies the fuel. The bottom line: 108 hp at 10,500 rpm and a broad torque curve.

Honda's third-generation, linked-brake system provides the stopping power. Pull the front lever, and four of the six front pistons and two of the rear four pistons grab the rotors. Push down on the rear brake pedal, and two rear and two front pistons go to work. A well-tuned system of proportioning and delay-action valves smooth the linking process. It's hard to tell the brakes are linked, but the benefits are easy to recognize.

The aluminum perimeter frame, based on Honda's "tuned flex" philosophy, features stiff engine cases that carry the rear single-sided Pro-Arm. A new twin headlight and thinner and lighter digital instrument cluster add to the more aerodynamic body.

Motorcycling can be a risky undertaking, but rider safety classes help decrease the risk. So does the VFR. Classified as a sport-touring bike with a semi-tucked riding position, the VFR puts the rider upright enough to be comfortable and have excellent vision, but low enough to connect the rider with the machine.

The systems work together so well that they improve your riding ability. You can stop faster (linked brakes), maneuver through corners with confidence (new chassis), and accelerate out of harm's way (new engine). The chassis handles road irregularities, such as patched-over asphalt and freeway construction, without any squirm or waddle.

Custom ride. I increased the rear rebound damping to match my weight and riding style--the rear adjusts for damping and spring preload, and the front for spring preload. This adjustment significantly reduced quick, jerky ride motions and can help instill confidence. A sudden panic attack can wilt your ability at best and, at worst, freeze your body so that performing any action to deal with an unexpected situation becomes impossible.

To date, the only failure to report has been a leaking front fork seal. The dealer replaced it promptly without cost or question. The engine has not leaked or used any oil. Nothing has vibrated or broken loose. The fuel injection is right on, the engine starts easily, and cold drivability is flawless. Fuel consumption averages a decent 39 mpg, which means the 5.5-gal tank can take you about 190 miles.

The Honda engineering team has done a super job, artfully using technology to advance riding safety and pleasure. What else would I add or change? Maybe I could get some of those little whistles that are suppose to scare deer. However, that might trigger more buyer's remorse.

Richard A. Herald
Project Engineer
Golden Engineering Inc.
Centerville, IN