The Service Department
THE SERVICE DEPARTMENT
GORDON H.JENNINGS
BMW RIDERS VERSUS THE WORLD
I would like to take issue with some of the statements you made regarding the Norton Manxman. First, it was stated that “in the area of road-holding and braking they have no equal.” Apparently your tester is unfamiliar with the BMW.
Secondly, you say that “it can be honestly stated that it (the engine) is set into the finest frame and suspension package that can be purchased today.” Again I refer you to the BMW.
Regarding the brakes you say “it is unlikely that better brakes are to be found on any other sports/touring motorcycle today.” How about the BMW’s twin leading-shoe brakes?
Finally, you say “in its element, which is fast highway cruising, the Manxman has no peer.” I can only say that when your tester takes a ride on a BMW he will realize how crude the Norton really is. It is, of course, unfair to compare the BMW with any other motorcycle.
Now for some of my pet peeves regarding motorcycles in general. Chrome fenders and tanks 1 regard as idiotic. And, why on a road machine are different size tires mounted? That alone would keep me from buying a motorcycle so equipped.
Why too, in the name of common sense, are oil tanks still hung on the frame; apparently as an afterthought by some engineer? BMW, and others, have solved this problem.
Herbert Hanseman Penryn, Calif.
Well Herbert, I can understand your partiality toward the BMW, but let’s not lose our heads over this thing. We will defend our opinions of the Manxman to the end: insofar as the matter of braking is concerned, the Norton’s single-leading shoe units may be at a slight theoretical disadvantage, but they stop the machine in an entirely satisfactory manner — and that is all that can honestly be required.
In the area of handling, the Norton is more stiffly-sprung than the BMW and is consequently its inferior in comfort, but in terms of pure, high-speed road holding the Manxman is superior in every way. Should you think that this is merely our personal opinion, please restrict yourself to doubting thoughts as to the value of our judgment. Do not get into any fast ear-holding contest with a competent Manxman rider. The experience may cost you some skin. As for your comment accusing the Norton of crudeness, we can only conclude that you have most curious standards by which you classify motorcycles.
You are, however, quite correct in one respect: it is wrong to compare the BMW with any other motorcycle. The BMW is superb in the role for which it is intended, long-distance touring, but it is no great shakes as a scrambler, or as a fast sports/racing bike. Obviously, it is not intended as either of those things and it is pointless to make comparisons.
As for your pet peeves: yours seem to be more emotional than rational. The chromium-plating is a matter of personal taste, and the Romans settled that question over 2000-years ago with the saying “De gustibus non disputantum est” or, (taste cannot be disputed).
To continue: motorcycles wear tires of different sizes and patterns because the front and rear wheels do not have the same job to do. Using the same tires at both ends may satisfy one’s sense of neatness, or reduce the problem of logistics, or — in the case of the BMW — make it possible to use the spare tire carried on the sidecar on any wheel, but there is no compelling reason why a solo bike should have identical wheels and tires.
Finally, the position of the oil supply will always be determined by the type of lubrication system used. Wet-sump engines, like the BMW, must have the oil reservoir underneath the crankcase, where gravity pulls the oil after it passes through the bearings. Dry-sump engines, which have scavenging pumps that pick up the oil from the bottom of the crankcase, keep their oil supply in a separate tank that may be mounted anywhere. Each type has advantages: the wet-sump system is neat and simple, and free of potentiallyleaky external oil lines. But, it adds to the height of the engine, and is more prone to oil contamination from combustion “blow-by” than the dry-sump system. With the dry-sump, oil-leaks are more apt to occur, as I said, but the oil supply is kept cleaner and more oil can be carried. Also, for reasons we will not go into here, there is less chance of the oil-flow stopping at high engine speeds. And, too, the engine may be lower, which is a great advantage on a large-displacement engine. This type of system chosen will depend on many factors and I would not simply out-of-hand condemn any designer’s final choice.
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This philosophy I woud recommend to anyone, not just with regard to oiling systems, but toward motorcycles in general. There is no motorcycle made today that is utterly without merit, nor is there one that is absolutely perfect. The one-make enthusiast would do well to recognize this fact, and to try a great many bikes of the general type that interests him before drawing any firm and final opinions.
DISCS DANGEROUS?
Read your article on disc brakes with great nervous twitches. Believe me, l think disc brakes are fine, but wow! On a cycle — and both wheels from ONE master cylinder!!?
One rule l never forget: the front wheel on a motorcycle encounters all road conditions before the rear. Picture this situation: rounding a bend (not too fast) a need for moderately heavy braking, then a bit of gravel or sand on the roadway. If that rear wheel is on the verge of a skid when the front tire hits the sand — bye, bye baby. And no individual control — double wow!
Chuck Honodel Livermore, Calif.
Under the special set of circumstances you give, it seems to us that a case of pavement-rash is in the offing no matter what you do. Like everyone, we have rounded corners and found ourselves on sand or gravel — and if you can do any braking, with either wheel, on such a surface, you are a better man than anyone here. The only thing we have found that was effective is to simply drop one foot and try to “dirt-track” until we ran out of the sand. And, on the rare occasions when there was too much speed, and too much sand we just naturally have to “step-off.” This is, of course, the procedure for slow bends. Hit that same patch of gravel while flitting along at a fairly high rate of travel and you unload so quickly that there is no thought of getting a foot down, or the brake on, or anything else.
Actually though, we do not doubt that there are circumstances in which the single control feature is a disadvantage.
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On the other hand, it is possible to conceive of conditions under which a steering wheel would be better than handlebars, and a fuel tank towed along on a little trailer better than one mounted above the engine.
As we recall, arguments similar in nature to the one you advance were being used when the great “hand-shift versus foot-shift” controversy was being waged. In the end, the foot-shift proved to work best under most conditions — and we think the some thing applies in the case of the single-control braking system.
FUEL CONSUMPTION
The two road tests in the May issue lead me (falsely, I hope) to believe that you are using factory-published gas mileage figures.
For the Maico 250 you say “Fuel consumption . . . n.a.” Why? If you have the Maico, and the Maico has a speedometeri why is the fuel consumption “not available”?
And, for the Honda CB 77 you show a range of 60 to 90 mpg. This sounds unrealistic. I ride a Honda CA 77 (same basic engine, but in a heavier bike and with one carburetor), and my best normal driving mileage has been about 55 mpg. Of course, driving habits and state-of-tune have everything to do with gas mileage, but my habits are conservative (for California freeways) and my bike is maintained by one of the best mechanics in the country.
Please tell me I’m wrong; I enjoy your road tests too much to lose faith in them over such a piddling point as fuel consumption.
E. N. Story Richmond, Calif.
As a matter of absolute fact, Mr. Story, we don’t place a lot of faith in the exactness of our fuel consumption figures ourselves. In the time we have to devote to road testing, it is difficult to put enough miles on the machines to get a really accurate indication of consumption rates. A motorcycle burns so little fuel that it is almost impossible to get a firm average in less than two to three thousand miles of riding. Further, there is a serious problem in the matter of miles covered.
We have discovered that, like the speedometer itself, the odometer is often wildly innaccurate, and although we calculate in a correction factor for this, the error cannot be completely eliminated — owing to the fact that the error changes with speed.
Finally, the errors are magnified by the large numbers involved. A ten percent error at 15 miles per gallon is only 1.5, but the same error at 55 miles per gallon is 5.5. This basic lack of exactness is one of the reasons we give a large spread in the mileage range. In the final analysis, we may be wrong in presenting any figures at all, as they are liable to errors up to 10 or 15 miles per gallon. However, we do get a reasonably accurate indication of the mileage range and we have decided that it should be presented with the rest of the data — of which we are a great deal more certain.
To answer your specific question about the use of “factory” figures: we do not, no more than we take their word in matters of speed and acceleration. Indeed, we do not even know, offhand, what Honda claims for the CB 77. As for the Maico, as you will notice at the bottom of the data page, under the heading of speedometer error, it had none — and lacking that instrument, it is very, very hard to get any figures at all.
