Shift-shaft voodoo, how does it select?

[OK-944]

I've got my trans out, and have just installed Only944's short shift kit and shift linkage kit. Went on great...very easy with the trans out of the car.

Then, as I looked at the linkages, I'm thinking to myself..."how does this setup, with but one rotating input shaft into the actual trans itself, somehow coordinate with a variable angle shift shaft...to know which gear to select?

That linkage which goes across the top of the trans just goes to an anchor point, and while it is linked to the shift mechanism via. two ball joints, the aforementioned attachment point is a fixed, threaded anchor - with no other function.

The shift itself is accomplished by a single shaft, which, although it has multiple stops for different gears, only rotates on a single plane...while the gearshift shaft itself changes its angle of attach based on the position of the gearshift lever in the cabin.

My question is how, through what kind of voodoo... do these angular changes facilitate specific shift changes, and do this in an accurate, consistent manner? What am I missing here? Just curious!

[Stoneguy]

https://www.youtube.com/watch?v=saezZQddRzE

See if this helps with understanding operation

[azbanks]

The shift rod slides forward and back and rotates left to right. The shaft that goes into the transmission case gets pulled up out of the case when the shift rod rotates left and gets pushed down into the case when the shift rod rotates right. The shaft rotates forward and back when the shift rod moves forward and back.

[CaraSmock]

Selector shafts serve to transmit shifting movements and/or selection movements from a driver or an actuation system to a standard transmission, for example to a change speed gearbox. During the shifting or selection process, the selector shaft is moved or pivoted about its longitudinal axis.
official website

[OK-944]

So...the transmission-mounted shift cylinder, in addition to rotating...also moves in an out? Not apparent when I mess with the mechanism on top of the trans...but it makes sense. Maybe I'll grab the cylinder and give it a pull (or push) so I can see for myself.

[azbanks]

Watch the video Stoneguy posted. You can see the shaft that goes into the transmission rotate and move in and out of the transmission.

[thomasryan]

there are three rods in the transmission. moving the shifter left to right rotates the linkage to each.

the fore and aft motion of the shifter, slides the chosen rod for first or second, third and fourth, ect

[Ernie944]

Lol...Do you ever make life complicated for yourself ,just install it and enjoy have a good day

[Stoneguy]

Ok-944,
I have the same curse as you seem to have.
While I pride myself on problem solving ( Mechanical things) I find I am never satisfied with the fact that something just works.
The OCD curious side of me wants to know how and why!
It's not a bad thing, understanding sequence of operation.
Although sometimes it DOES drive me, and sometimes others a little crazy.

But isn't this why we tinker?
It's therapeutic!!!

[OK-944]

Thanks for your understanding...Mr. Stone!

I still have some time with my tranny out...and imagine that I'll tinker with the shift mechanism just a bit more to see if I can get the rotating shaft to do anything but rotate on one plane, before I reinstall it and let the voodoo commence once again! Right now...I still can see no possible way that slight changes in shift shaft angle could in any way influence the tranny's behavior!

[azbanks]

Originally Posted by OK-944

Thanks for your understanding...Mr. Stone!

I still have some time with my tranny out...and imagine that I'll tinker with the shift mechanism just a bit more to see if I can get the rotating shaft to do anything but rotate on one plane, before I reinstall it and let the voodoo commence once again! Right now...I still can see no possible way that slight changes in shift shaft angle could in any way influence the tranny's behavior!

Did you watch the video?

[OK-944]

Yup...watched the video - makes perfect sense!

Still cannot get this action to happen with the tranny out...but will trust that all will be well after its back in!

[azbanks]

It takes a lot of force to make it move in and out.

I found this video that is pretty good at explaining what is happening inside the box.

https://www.youtube.com/watch?v=JOLtS4VUcvQ

[Stoneguy]

https://youtu.be/UxJWBUCJZMA


A little more in depth 944 Transaxle info.

[maint]

OK-944 I'm glad you asked. I recently adjusted my linkage when installing new shifter and thought the same thing. Now I know