I used an old, scrap brake rod to mock-up the linkage between the lower arm and the stub of an original Bultaco shifter. This is just a quickie proof-of-concept. The real component will be an alloy clevis threaded to a spherical joint at the bottom, which should eliminate some free-play.
I had to re-bend the shift pedal just so. I discovered that there’s barely enough clearance for it between the arc of the kickstarter and the shift linkage, but it all clears as it’s positioned now.
