Dave – Silly old Duffer +1
Tony
There is of course a world of difference between manufacturing and modifying motorcycles or vehicles.
In the early 1970's i was inspired by an article in Motorcycle Mechanics? to modify a BSA Bantam to produce a trials bike. This entailed fitting C15 forks and steering yolk, the stem required shortening to accommdate the Bantam headstock. Various other "modifications" including the fitment of a George Todd cylinder head, obtaining a barrel ready ported, (why reinvent the wheel) fitting crankcase and flywheel stuffers to my own design, but no doubt from inspiration gleaned elsewhere. I toyed briefly with a Wal Phillips fuel injector and made an expansion chamber modified to accomdate a high level rather than a low level exhaust. As more knowledge was required than I possessed I have no doubt I copied the design.
I fitted alloy mudguards, fitted a home produced single seat and various bracketry to suit it is unlikely other than a rough sketch to note dimensions I would reach for the drawing board.
I am currently nearing completion of a pinfire percussion cap and pin insertion tool for an RFD friend of mine, "copied" from a proprietry Hawksley/Bartram 12 gauge device, Why reinvent the wheel? I drew a sketch and transferred the dimensions, I then on a similar sketch reflected the reduced dimensions for the 16 gauge tool I was actually making. The simple dimensioned sketches I produced facilitated ease of manufacture without the need to constantly measure and reduce scale with the attendant risk of error. I devised a form tool to create the external profile of the cartridge head and set up my tailstock turret with Rotabroach and milling cutters to machine the internal features, all with idiot proof depth stops.
I also I have also made a fixture to drill the hole for the pin in the cartridge head and a second tool to complete the machining for the cavity to accomodate the percussion cap, both produced from my imagination and dimensioned sketches. As the original cartridge heads were pressings and my alternative is machined from solid brass there was nothing to copy for this stage of manufacture.
Also on the stocks is a pedestrian lawnmower service stand, which has progressed through several redesigns sketched on paper, some of which were inspired by internet searches. My early designs have transformed into something almost fit for purpose without any wasted materials or time. Once I am happy I will start manufacture.
In truth you are "modifying or customising" a previously manufactured motorcycle and there is no harm in that, Also what you have made appears to be well executed. However what I and a number of other Forum Members took exception to is the ascertion that if member needs or produces a drawing to make something they lack imagination or skill. Further as has previously been mentioned if your posts are provocative you must expect a response in similar tone.
Robert Butler