What I decided to do was use the Autocom cable, but replace the switch with something more suitable. After some weeks I finally came up with this arrangement, a PTT button mounted on top of the clutch lever operated by my index finger. For me it's much easier to use, it doesn't crowd the handlebar and the radio never gets left on permanent transmit!

First thing was to find how the original switch was wired, so after removing the single Philips screw that holds the PTT switch together and prising the shell apart, all was revealed. The bit I'm interested in is the blue 'tactile switch' attached by the grey and blue wires. It's a 'push to make' switch with added click! Tracing the wires back to the cable they changed to red & black, then in the cable itself red & screen.

With the colour codes now known it was simply a matter of cutting the original switch off and fitting my own. In the picture below the Autocom cable is on the left, the new PPT button on the right. I spliced the red core straight through with a soldered joint and heat shrink sleeving. The Autocom cable screen was then soldered to the new PTT button black wire and the unused blue conductor in the Autocom cable had a heat shrink fitted to stop it shorting to the screened conductor. Once that was done another larger heat shrink sleeve was fitted over the whole joint.

Testing the new PTT button, the radio is a Puxing 777 Plus tuned to PMR 446 frequencies and 500mW output, it seems to work well on the standard Autocom / Kenwood radio cable.

Fitting was easy, after threading a draw wire along the left side of the fuel tank from front to back behind the bodywork, I was able to attach the new PTT cable and pull it through to the front of the bike. (I was unusually lucky - it went through first time). To mount it to the clutch lever I cut 35mm of old bicycle inner tube and pulled it over the clutch lever adjuster to create a none slip surface, then simply tie wrapped the switch down with two thin ties. The PTT cable was then run neatly with the existing cables back through the fork legs.

Tested and working, and as I usually rest my fingers on the clutch lever, I find it very convenient to use. Much better than the thumb button!

Notes:

1) If you need to extend the original Autocom cable, try to use screened cable to help prevent interference on the radio transmission.

2) When you cut the Autocom switch from the cable, leave at least 6" of cable on it so you can re attach it later.

3) Do check how your Autocom switch is wired internally before starting, it may be different to mine.

4) The heat shrink sleeving came from my local B&Q Warehouse and was very reasonably priced, use a match or lighter to shrink it down.

5) Take care when threading your cable through the bike blind, be sure it isn't caught up in anything that matters, like the throttle controls!

6) Finding a suitable switch is of course key to this project, a waterproof microswitch with a short operating arm would be ideal and would only need a nudge with the index finger to operate.

7) The PTT button I used is from an old Alan MHS300 Headset kit [see picture below]. The button and strap assembly unscrews easily at the back leaving you with just a push button on a cable.

Lastly,  If anyone from Autocom reads this, then perhaps you might like to make a factory version to save us all the bother, thanks guys! :-)

Disclaimer

This page is offered as a guide only

Any work you carry out on your motorcycle you do so entirely at your own risk