I had intended to talk about the design process for the rear frame that holds the luggage, but that was before the constructed frame threw up some issues that I hadn't taken into consideration at the very beginning. The design is unusual in that the frame goes around the luggage rather than underneath the luggage. This serves to centralise the weight of the luggage by carrying it closer in and also acts as crash protection so that the frame rather than the luggage itself takes the brunt of any fall which allows the luggage itself to be of a much more lightweight construction. In brief, the outline of the frame was originally laid out in wire on the bike itself, to check clearances and ensure the visual lines of the luggage frame matched those of the bike frame itself. This outline was transferred into steel that I formed with a tube bender and then welded up using oxy-acetylene to the second mounting point so that the frame was strong but at this point still quite flexible. Once the positioning of the frame was set it was then triangulated for stiffness and additional strength. This added strength is such that the frame is now stiff and strong enough to lift the rear of the bike off the ground from a corner with very little detectable flex. It was only once the structure of the frame was complete and my mind was moving to starting to build the luggage to fit inside the frame that I noticed a serious flaw in its design. Missing from the factors I took into consideration when designing the frame (e.g. exhaust position, body position of the rider, suspension travel, access to luggage, crash protection, etc...) was the travel of the kickstart and whether the frame interfered with it. Without any cause to start the bike for some months while it's being torn down then built back up this may have gone unnoticed for much longer but the realisation I had missed it struck me in bed early one Saturday morning... The travel of the kickstart was only just interfered by the frame: ...but that was without taking into account the heel of the rider hanging off the back of the level while kicking. A remedy would have to be found. By welding in a piece further back then removing the original line I would be able to remove the original the frame would retain the original mounting points and lose only a little luggage space behind it while ensuring the frame did not interfere with the kickstart. With the new line welded in and the old cut out I then welded in caps to the ends of the tube: Which when mounted back onto the bike gave all the necessary room to kickstart levers and heels:
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February 2017
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