A GAS-JET injects the fuel (Butane or Propane/Butane Mix) into the mixing chamber to combine with the air. Just like a fuel injector or carburetor in a car,
you can make your mixture richer or leaner by changing the size of the outlet in the nozzle.
NOTICE:
This is only a description of what I chose to do to my own RUBY engine. It in no way is meant to encourage others to make this or any
other modifications to their equipment. This is a minor modification and can easily be undone. Exert EXTREME
CARE and remember to MEASURE TWICE / CUT ONCE! Again, this is what I did and how I did it. It worked for me but NO guarantees are expressed
nor implied that this is the way any sane person would accomplish this task.
Pull out the original equipment gas jet. If you're Ruby has a copper supply line, disconnect it from the gas reservoir and remove it with the jet. Cut a length of silicon tubing to the appropriate length. I wrapped my ends with some spare wire, but clips are also available.
From the 'DO AS I SAY NOT AS I DO' Department: There is NO SUBSTITUTE for the RIGHT TOOLS. If you should decide to attempt a similar conversion,
I recommend having a Dremel or similar tool with cutting and grinding bits, a drill (Drill Press preferred) with an assortment of small metal bits, small metal files, TUBE BENDERs of
the appropriate size, a good hot torch, and all SAFETY EQUIPMENT! Nothing is worth an eye or a hand!