TRM
Wore out three sets of tires already!
I was asked to post some pictures of the shift linkage that I made to replace the original cable shift for a Dana 3 speed transmission on my Raceliner bike.
Here are some pictures and a brief explanation of what's going on.
This is how the tranny looked when I opened it up to rebuild it.
The boss for the original cable shift is made of plastic. It's the white plastic piece in this picture:
I didn't feel that attaching something directly to the plastic would hold up over time, so I made what is essentially a socket to fit over the plastic shaft. It just so happened that the top of the seat tube that I had cut from the frame was just the right size and even had a collar on it that saved me a step.
Next, I fabricated a bridge piece to hold the 'socket' in place and allow it to turn.
Everything up to this point was designed to give me a metal shaft in place of a plastic shaft to connect the linkage. Then, after a lot of playing with the geometry to make the longer shifter movement work with the shorter shaft rotation, I made a lever mount for connecting a heim joint.
To finish the linkage, I mounted the shift arm (originally a Ford column shifter) with an opposing lever mount welded to it, and connected the two points with a connecting rod made from a piece of stainless brake tubing.
In the end, it shifts very easy and smooth!
Here are some pictures and a brief explanation of what's going on.
This is how the tranny looked when I opened it up to rebuild it.
The boss for the original cable shift is made of plastic. It's the white plastic piece in this picture:
I didn't feel that attaching something directly to the plastic would hold up over time, so I made what is essentially a socket to fit over the plastic shaft. It just so happened that the top of the seat tube that I had cut from the frame was just the right size and even had a collar on it that saved me a step.
Next, I fabricated a bridge piece to hold the 'socket' in place and allow it to turn.
Everything up to this point was designed to give me a metal shaft in place of a plastic shaft to connect the linkage. Then, after a lot of playing with the geometry to make the longer shifter movement work with the shorter shaft rotation, I made a lever mount for connecting a heim joint.
To finish the linkage, I mounted the shift arm (originally a Ford column shifter) with an opposing lever mount welded to it, and connected the two points with a connecting rod made from a piece of stainless brake tubing.
In the end, it shifts very easy and smooth!