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  • On 3rd March 2015

“Think left and think right and think low and think high. Oh, the thinks you can think up if only you try.” Dr. Seuss

I am not a designer.   I only found myself forced to think about “design principles” in order to keep this project manageable; confined within certain boundaries.  After all, it had to be finished.

As I spent hours looking at the bike in the workshop and as the notion that I would eventually have to work on every single part of it forced its way through and became “law”, I realized it might just be a little easier if I had a few rules to guide me through the decision making and all the thousands of choices.

At first sight, the CB550 engine appears simple to the eye in its uniformity of silver colored components, which just blend into each other without calling any attention to themselves.   It gives the impression of being just a single piece of metal that is indivisible.  But behind that façade is a staggering complexity. There are 4 cylinders, 4 spark plugs, 4 carburetors, 4 header pipes,  4 header flanges, 8 tappet covers, 8 cooling fins in the cylinder block, 12 cylinder head mounting nuts and rods, 28 bolts holding the engine together, 56 cooling fins on the cylinder head, etc.  It is amazing what you can discover if you stared at something long enough!   Most everything was seemingly divisible by 4, or, for sure, divisible by 2.  It suggested symmetry.

The more I looked the more I realized that the prevailing shape was that of things being “round”. The wheels, the hubs, the sprockets, the alternator cover, the points cover, the speedometer, the tachometer, the headlight, the brake disk/rotor, the caliper, the mufflers’ openings, the gas cap’s contours, the curvature of the fenders and  gas tank,  etc.  There were curvatures, in most cases complimentary, everywhere I looked.

Anyone starting with a “blank slate” and building from there must face the temptation of available choices in color and technique.   Anodizing, chroming, powder coating, color blending, air brushing are only few of the myriad of available tools that can be used to create any appearance no matter how wild the imagination.  I had to choose mine.

These were then the 3 principles:

  2. FORM
  3. COLOR

As important as such principles may be, they certainly appear to be too vague in their broad definitions.  They sound great and seem to have an aura of significance to them.  But, I didn’t have much time to ponder the theoretical importance.  I had to find a practical application.

One way to apply the principle of symmetry was that if I were to split the bike in half along left and right, everything on the left side will be more or less a mirror image of what is on the right.

To apply the principle of form in any practical way would require that the majority of the components would be designed along similar lines of curvature and that when put together there would be hopefully a seamless transition.  At a minimum, nothing should be obviously jarring.

Deciding on color was even easier.  I have no ability to match colors and my preference is to retain simplicity.  So, the decision was quick.  The color will be black accented by the natural silver of aluminum and steel, and the natural yellow of brass.


The front view of the bike below shows the left/right symmetry of components.  Note the near perfect line of symmetry for the header pipes, header flanges, and engine, including the tappet covers and taillights.  The foot pegs, brake pedal and gear shifter are seemingly slightly out of symmetry due to the fact that the bike is leaning on the kick stand.

Front symmetry

Note also the symmetry of the brake and throttle cables (painstakingly measured and tried using old cables prior to fabrication of the new ones) routed so they cross over exactly in the middle of the line of symmetry.

Custom stainless steel handle bars and cables

Custom stainless steel handle bars and cables

The rear view below shows a similar symmetry (accentuated by the yellow band, itself symmetrical, running through the middle of the tank) of the mufflers, taillights, shocks, handlebars and grips. (Note:  I was initially tempted to do what other bike builders had done in using a single taillight, either a replica of the Vincent Black Shadow or a Ford truck, positioned low on the frame as well as the curved license plate holder rotated at 90 degrees to “normal”.  But these ideas violated the symmetry principle and it was so easy to resist the temptation.  I had to use two taillights (probably the only compromise I made to the principle of reducing weight) and a license plate holder running right down the line of symmetry. )

Symmetry 1


Being more subjective that the seemingly scientific and easily measured line of symmetry, the execution of the form principle is difficult to ascertain objectively. The overall appearance of the complete bike is perhaps the final arbiter and everybody has to decide for themselves if there is good balance.  I just want to say that I followed the form principle as much as I could and was guided by it in deciding the shape of the bobbed rear fender, tank, seat, handle bars, headlight, taillights, etc. including, perhaps importantly, the decision to use a front wheel hub that matched the shape of the rear one and lacked the asymmetry of having a brake rotor on one side only.  The pursuit of similarity in form is also apparent in the fact that the BLACKSQAURE logo on the tank follows the tank’s curvature. The taillights’ brass visors, the mufflers’ hanging brackets, the front brake stay and the custom brass chain adjuster bolts all conform to the same principle of “curved or round”.

Here is a closer look of the rear fender, seat and tank (the white horizontal white lines in the background are there “by design” (not photo-shopped) as they provide a “shape” reference to the curvatures of the bike’s components):

Seat and Tank 2


The only painted components on the bike are the tank and side covers.  The frame and swing arm are powder coated.  All metal surfaces are either bead blasted, wire brushed or polished.


I owe it to fellow bike aficionados and curious readers to acknowledge the contradiction between the FORM concept of “curved or round” and the square shape in the BLACKSQUARE logo.  And for that matter, why BLACKSQUARE?

I don’t think I can give a satisfactory answer other than to say, “It seems to work.”  Perhaps the square provides a shape frame of reference against which the curved shapes tend to become better apparent. Like when the perfect stillness and enormity of the glass-like smoothness of the water in a lake becomes apparent only when a small pebble is dropped on it?  I don’t know.

But a contradiction is present and nothing I say can take it away.  To the purist, such a contradiction may not appear complimentary. In this case perhaps the best consolation we can find is in the last line of the movie SOME LIKE IT HOT, which the Osgood Fielding III character delivers so nonchalantly:

“Well, nobody’s perfect.”


1 Comment

  1. Terry Mayes · March 5, 2015

    Wow, I had a CB 400 for a while. Dumped in on a corner with sand, and totaled it, and nearly myself.

    Well written documentary, well executed mechanically.

    Very Nice