How to Complexify a Choke Cable

My TR6 had a dual choke cable with solid inner wire.  For reasons not important here, I wanted to operate the choke levers on the carbs with flexible stranded inner wires.  Determined to re-use as much of the original control cable as possible, I came up with a hybrid control cable.

I started by pulling the inner wires out of the original cable and cutting off one of the two outer cable sheaths right where it emerges formthe control head, and cutting the other sheath so it would just make it through the firewall.




This is a Bowden cavble splitter.  One cable comes in one end, and up to four cables come out the other end.  The little brass shuttle inside connects all the inner wires.  It is designed to split sthrottle or choke cables for multiple carbs.




Though these devices are intended to work with stranded inner wires, there isn't any good reason they won't work with solid wire, too.  You just can't plan on having a "push" action transmitted through the splitter because of the way the inner wires are terminate in the shuttle.

I soldered a little brass wire end onto the solid wire of the old control.  Similar to the process for stranded wire, I "upset" the end of the wire so the wire end was mechanically captured before soldering.




Then I made a couple of short cables with stranded wires to go to the carbs.




Putting it all together and installing it, it was quickly obvious that the return springs on the carbs would easily pull the control back to the home (unchoked) position since there was no locking mechanism on the control head.  (Locking wasn't necessary with the solid wire cable, since it can both push and pull, and return springs at the carbs were not used.)

So what was necessary was some controlled drag on the cable to just balance the spring tension.

To do this, I modifided the splitter by making a new end cap that was a little longer and included a set screw that would push on a little nylon pellet that in turn pressed on teh solid wire from the control head.  Drag could be adjusted with the set screw.




So here is the thing installed and working.



In the end, although I got it to work well, I decided to scrap the design.  It is complex, a minor hassle to set up and adjust, and works no better than the stock design.