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2006 GSA Tach Signal

To be clear - you want a tach (engine rpm) signal.
Not wheel speed.

Yes. I’m installing a Rosta electronic cruise. It uses both a VSS, which I hooked into using the empty cruise control harness plug, and a Tach signal. I’m having trouble finding a wire to tap into for the tach.
 
The instrument cluster signals are via Can Bus. There is no separate signal to the tach.
I would suspect the Crankshaft encoder (at the top of the engine under the alternator) could give you a signal.
It is a 2 wire device that would appear to be a magnetic pickup - AC signal.

It plugs into the harness and ends up at the engine control unit.
Yellow wire to pin 72 - KWG-
Blue/yellow wire to pin 71 - KWGs
 

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The instrument cluster signals are via Can Bus. There is no separate signal to the tach.
I would suspect the Crankshaft encoder (at the top of the engine under the alternator) could give you a signal.
It is a 2 wire device that would appear to be a magnetic pickup - AC signal.

It plugs into the harness and ends up at the engine control unit.
Yellow wire to pin 72 - KWG-
Blue/yellow wire to pin 71 - KWGs

How would I tap into this to get a signal? What would be the best way?
 
How would I tap into this to get a signal? What would be the best way?

1) Ideally one would need to make a male/female interface connector that would fit between the sensor and the main harness
You would need an old wiring harness and salvage the parts from it.

2) At the harness side of the 2 pin connector. Unwrap the sheath and Positap or Solder/heatshrink

3) At the interface connector to the module. The protective cover can be slid off and all the wires accessible.
How you connect is your choice, solder, positap etc.
Wiring is tight together so be careful.
 
I have to ask- what did the instructions have to say with the kit?
OM
The instructions don’t say where to attach the tach sensor wire. It just says do it so the system will sense a Tach speed up and disconnect the cruise automatically. It gives no info on where you actually attach the lead.

The instructions say the cruise will work without the tach lead hooked up but it won’t disengage automatically since it can’t sense tha tach change.
 
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I have installed 2 of the Rostra electronic units on R1200gs. On the 06 I used the gps feed wire that contains the vss Signal and power feed. I connected the brake control wire and didn’t use the tach or clutch switch. Works fine as it would on an automatic transmission vehicle, but you do need to touch the brakes to cancel the cruise. Never tried a quick 6 to 5 downshift to see how much the engine would rev. The response rate is adjustable on the unit. I would start with the V8 and slow response and work towards the correct speed control maintaining without excessive hunting. On the 2012 I had to pick up the Vss by adding a wire to the computer connector.
If you haven’t read this article from ADVrider please do so.

https://advrider.com/f/threads/electronic-cruise-control-installed-gs.845862/
 
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