I have a 89 tour glide classic....trying to install a new speedo cable...I got the top half out of the speedometer, but nothing is happening but spinning on the drive unit? the new one has threads, so I assume the bottom does too, but ive tried twisting at every point and its doing nothing but spinning.....is it a one piece drive and cable on the oem part? or what am I doing wrong?

 

You should be able to grab the cable with a pair of pliers and spin the drive unit off.
I have always done it with the drive unit off the bike.

 

The bottom end of the cable "screws" into the speedometer drive. I think there is a small set screw in the drive unit the locks the cable into the drive.

 

You will need to grab hold of the bottom part that goes into the drive ,it threads into the drive.

 

that was the problem...the setscrew...well its still a problem...wont budge...

 

Vise grips to get it moving .

 

Or use a replacement drive unit, they are readily available. I use a tv cable rubber sleeve to protect that lower joint, to keep water out. If yours has been left to the elements for a long time save yourself the bother and replace it!

 

i used shrink tube, it's used for sealing wires that are soldered together. get some that's big enough to fit over the drive and cable, apply some heat and it will form to the cable with a water tight seal.