There are gear position indicators available for 2008 and later model year ST1300's that plug in to the diagnostic connector and are plug and play. The 2007 and earlier model years are not plug and play. If I remember correctly, they must be individually wired in to a combination of the tachometer, speed sensor and clutch lever switch signals. I can't remember which combination of those three or if all three are required. It requires power and ground as well. It is not terribly complicated. There are detailed instructions of how to do it on this forum.
I have a Heal-Tech clone on my 2012 ST1300 that I sourced from Amazon. What I think I discovered is, Honda models with the appropriate modern diagnostic port (meaning 2008 & later) are truly plug & play, which my 2012 ST1300 happens to be. All of the necessary signals can be read through the ECU port.
2007 and earlier have a a different ECU and the data required by the gear position indicator (GPI) must be collected from different places within the bike's electrical system. Perhaps the best instructions, strangely come from Heal-Tech's own website as nearly every, okay every, GPI other than Heal-Tech's is a clone of Heal-Tech's and install with the same connections.
Here's a link to the installation document for the Heal-tech GIpro X-type G2 with the GPX-H01 Harness Kit (this is specified for the ST1300 2007 and earlier).
IIRC, all the connections can be reached under the right lower cowl just behind the motor, ahead of the frame. The speedo sender unit and its connector are in there. The other signal, which Heal-Tech takes from the ECU, well I can't tell you where that is on the 2007 and earlier models. It may very well come from the coil like the MC Cruise does. All the unit is doing is comparing the pulse frequency from the speedometer and the tachometer and associating that with a digit displayed on the GPI. Within each gear, the ratio between those two will be fixed for any given road and engine speed.
Here's my thread on the topic, but it's for a 2008 and later design.
So as the arctic extended it's chilly tendrils across North America in mid-February I decided to finally pull my instruments and send them to BLUEGAUGES.COM for an LED upgrade. I weighed the pros and cons of doing it myself. If my workplace were unrestricted I'd have both ready access to the...
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