Letters
LETTERS
SAFETY SUPPORTER
Since I've read the Harry Hurt/ NHTSA report I have re-read, analyzed, advocated and promoted it to anyone who would listen. I even changed my style of riding. Tonight some of these changes probably saved my life.
I am a 24-year-old college graduate with three years of dirt bike experience prior to eight years of street riding. I have 13 months and 12,000 miles of commuting experience on my present bike. I have ridden consistently about 10,000 every year since 1972.
I was south bound on a one-way, two lane major street on my Kawasaki KZ400 cafe racer, one block from my destination. There were three cars moving ahead of me toward a red light. The light changed be fore we stopped so we all began accelerat ing. The first car passed through the inter section and the next thing I heard was very close, loud squealing tires. The second car stopped into the intersection without warning and the third car was trying to avoid a read-end collision. I swerved to the right and accelerated. I then realized an ambulance was speeding towards me on my right. My fingers were already on the
front brake lever and I came to a com plete, controlled stop three feet from the side of the ambulance. -
I feel sure if I had not had my fingers already on the front brake lever I could not have stopped in that short of distance. I could not have remained upright and in control only using the rear brake.
Because! studied Dr. Hurt's accident statistics, I avoided becoming one. -
Eugene W. Smith Manchester, N.H.
TAPERED ROLLER BEARINGS
After reading your evaluation of my firm's tapered roller bearings in the July issue, I find it necessary to comment.
The very loads which react upon the steering heads of motorcycles, and destroy ball type races, are axial (thrust) in nature more so than radial (rolling). The tapered roller bearing is the only bearing designed to handle any combination of radial and thrust loads. Increasing the bearing cup angle will increase the ratio of thrust to radial rating. Other design factors assure proper operation under changing thrust loads and radial speeds. These factors are also applicable to the swing arm on motor cycles, and for these reasons, we equip every box-construction swing arm, that we manufacture, with tapered roller bearings on the nivot shaft.
The practice of installing ball type races in the steering head is a misapplication of that particular type of bearing. All of our tapered bearings are chosen specifically for particular applications, and we use only Timken brand, the highest quality bearing available.
As for the installation, the instructions have been changed to avoid any possible misunderstandings. One was supposed to use the chisel to tap off the lower race, not to break it. You are right, though in saying it was better to use a punch.
The GS750/1000 set-up was a special> kit, but it does utilize standard components. The difficulty encountered during installation, could have been minimized by using proper procedure. Working with a bearing removal plate and a hydraulic press, the Suzuki bearing could have been pulled off rather easily. If no press was available, then two pry bars, braced against the lower tree, could have dislodged the bearing, but first, you should have removed the grease seal. The use of a hammer only added to the problem b^ scarring the stem, and by possibly deforming it.
Was the stem accurately measured to determine whether it was within tolerance and still round? Was the bearing we supplied correct in size? Answers to these questions are necessary for a thorough evaluation. A cone (the roller section) should be a snug press fit. The tightness with which the stock cone fit, suggests the possibility of a slightly oversize or dam-* aged stem. Only through accurate measurements can the source of the problem be determined. A few minutes work with some emery paper helps at times such as these.
And what about the cups (framed races)? What is a “slightly-too-loose” foD us fit? Again, accurate measurements here would reveal either an oversize frame I.D. or undersize cup o.d. Our cups are now sized to within £ .0005 in. of the required size for a proper press fit. Every cone and cup is individually checked b<f fore packing and is guaranteed to fit properly.
One converts to THB because he or she, understands a basic fundamental of improved performance. Replacing those useless, misapplied ball races with THB will yield a bike with improved, smoother steering with unexcelled reliability, a greater degree of safety, and minimal maintenance. It is a one-time operation and should never require replacement. In over four years we have never had so much as even one failure.
Yes, they are the best steering head bearings on the market, and I trust they are now better understood.
William Myshkoff
Ringwood, N.J.
SPEAKING FROM EXPERIENCE
I’ve been riding since 1933 and have never known one instance in which I didn’t need a kick crank at some of the most crucial times. It really makes me wonder at the manufacturers of big bikes. Are the/ for real?
The batteries that are part of the initial purchase of a bike are for the most part fo¿ the birds. They begin to deteriorate and start their letdown after a year of heavy use. My 900 Kawasaki battery bit the dust> in just over one year, my 1100 LTD starter came apart because of a factory goof and now my nice new Yamaha’s battery has expired ‘temporarily’ and if it were not for the kick crank which I personally installed on the nob that the factory had left as an option, I would have had to push my bike to get it going. But now the 1980s don’t even have a nob and that is sad.
I’m wondering if the manufacturers are giving the public what it needs or are they just suiting themselves? With my 47 years of bike riding experience, I strongly contend that the kick crank ought to have stayed. Do I hear pros and cons?
Art Armijo Carson, Calif.
AN ENTHUSIAST EXCHANGE?
First as an English reader of your magazine, may I congratulate you on the quality of your articles. It is a relief to find a magazine that assumes a high technical knowledge of its readers and then goes on to further that knowledge.
I am a keen vintage fan as well as an enthusiastic road racer and will be visiting the USA and Canada this summer. I would be pleased to meet any enthusiasts of motorcycling in any form and maybe even help with any problems they might have either on the technical or supply side of British bikes.
Andy Smith 70 Penine Avenue Sundon Park, Luton England
MEMORIES OF A SCOUT
Richard Renstrom’s story in the February 1980 issue about Ed Kretz and the Number 38 Indian Sport Scout was great.
I had a 37 cu. in. Indian Scout, leaf spring front fork and it was bored oversize.
I had the manifold polished and made into a stroker. It was then years older than Kretz’s and it sure wasn’t tuned by the Indian factory! We’d race it around a couple of half mile dirt tracks at maybe 45 mph at Southwest Washington fairgrounds and have a real ball. It would go pretty good on the straight too. We’d blow them out on the hard sand beach at 65-70 mph laying flat on the tank. There was no money involved in those days and we did it just for fun.
What a difference 50 years of motorcycle development has made! I now ride a 1979 KZ650, about the same size engine as the old Scout. I just ride for the sport and don’t care about 12 sec. quarter miles.
I like the smooth power and just humming along at 4500 turns, 60 mph and getting 50 miles to the gallon.
Joe Byington Tahuya, Wash.>
THE MOTORCYCLE IMAGE
I’ve had it. This time I feel I must do something. I am sick and tired of motorcyclists being portrayed on television as ruffians and lawless hoodlums. I’ve just seen an episode of CBS’s Knots Landing which featured a motorcycle gang terrorizing the residents of that community. The tone of the show was quite clear . . . motorcycles are noisy and destructive and the people who ride them have no respect for others’ rights or the law.
My experience tells me that such a portrayal could not be further from the truth. Virtually all the motorcyclists I know, or have ever known, are reasonably peaceful, law-abiding people. Their only transgressions have been an occasional traffic violation. But motorcyclists and motorcycling continue to have a poor public image, one that television seems all too happy to perpetuate.
After some thought about the matter, I have concluded that the most effective way of protesting television’s disparaging image of motorcycling is through economic pressure. This means not patronizing those companies that sponsor such shows.
I encourage you, your staff, and the readers of Cycle World to do likewise.
Michael P. Redgrave Minneapolis, Minn.
WINNERS THAT NEVER WERE
In the article “Winners That Never Were” (June, 1980), Gordon Schindler states that the idea of pistons of different size used in the same cylinder remains unexplained. A quick look at your nearest two stage air compressor offers a logical explanation.
To achieve higher pressures in compressed air systems, air is drawn from atmosphere into the larger cylinder (low pressure), compressed, pumped into
smaller cylinder (high pressure) and is compressed again. This concept can be applied to Allan Baker’s design by allowing the larger piston to travel to the top of its cylinder forcing its entire volume to fill the smaller cylinder. The smaller piston’s travel ends at a point short of the very top of its` cylinder and the remaining area becomes a high compression combustion chamber.
This system may or may not work, but it does allow compression ratios to be changed by changing cylinder bores in addition to more conventional methods.
Ross J. Cicero No. Ridgeville, Ohio
SETTING IT STRAIGHT
I noticed in your DR400 Suzuki test in the June 1980 issue that under specifications on page 45 the engine is said to be a two-stroke Single. But in the story it is stated to be a four-stroke.
This doesn’t bother me because I know the difference. Somebody else might not so please set it straight.
Mark Winter Concordia, Kans.
. . . And for our next dumb mistake. BÍ
