In the QBP catalog are 'problem solver' cable splitters, where 1 cable can pull 2, so with those a single cable can work 2 separate things.
meaning the shifter will still have just one cable..

coordinating them will require in line cable adjusters in each down stream cable housing..

your CGI is ok, in fantasy, but in the real world the suspension forks wont work at that low angle

and the trail will be immense, like a stretched out chopper,

consider a 20" wheel and a short suspension fork in a more standard 70 degree angle. re design of linkage needed,

because the arc of a wheel towards the inside of the corner is different than the radius described by the outside wheel in a turn..

Car's engineers sorted this out a long time ago.


a joy stick , hand crank with the brakes and shifters on the grips let your hands stay in one place ,
steering is a function of leaning the joy stick shaft to the right or left.




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