I was not that keen on the fuel tank or carb shown on the earlier engines so I decided to go for something similar to that made for the Midget, not least because I still had five of those miniature jam jars to find a use for!
Apart from having it screw into the cylinder head rather than use a flange mounting the only other real deviation was to have a lever to rotate the throttle barrel rather than using the actual jam jar. The CNC made quick work of this with a 3mm 3-flute cutter blending all the internal and external radii perfectly, I set the CAM to leave a couple of tabs so the part did not fly off part way through cutting and these were easily cay and removed with a needle file.
I used a piece of 8mm copper brake line for the exhaust which was filled with lead to stop it collapsing while being bent over a former. The lead melted out without sticking to the uncleaned copper and it was easy to silver solder on a short length of brass drilled 6mm and threaded M8 x 1.0mm so it could be screwed into the head and, like the carb, locked with a round nut with two spanner flats which I felt looked a bit nicer than the usual hex nuts.
That just about completes the construction.
Apart from the colour which was darker than I intended I'm happy with the way it turned out.
Here’s an option for anyone not keen on Kawasaki green.
Part five here
