Originally Posted by bonox
. . . the 12GS has [a two wire] inductive type
Alright well that's good then, it's the same type of inductive or 'VR' sensor as on the 1100/1150. So if we make something for your bike, it'll work for mine. I know it may not be the exact same sensor, but if it's needed, the signal conditioning circuit will be the same.
Tech side note: The R12 motor does not use a Hall Effect on the crank like the 1100/1150. It uses a VR sensor that triggers off the front of the crank. It makes its AC signal from the teeth of the counterbalance gear drive.
So I had to take a look at the signal from the rear wheel sensor on my bike. I'll double check later in case they are very different from your readings. I mean, the readings from the two bikes should be close. The number of ring gear teeth per revolution may be different for the 1200, but still.
The sensor resistance »
I was able to make a more or less steady 100 RPM for 15 seconds or so, and with a 77in. tire circumference . . . that works out to only 7.3mph.
At a wavering 7.3mph, the AC output wavers between 8 to 10mV.
That'd prolly be why your meter wasn't seeing it.
Put on a work glove and stick your index finger in the spokes and try to make 100 revs, it's tough. (Check the math if you want, I was wearing the beer goggles.)
Next you can plug the sensor back in and stick a thin gauge needle into the sensor wire to connect it to the meter you will be using. One meter lead to one sensor wire, and the other meter lead to ground.
Spin the back tire with the engine. You can ride around with the meter taped to the tank, or maybe turn the ABS off and drive the wheel while on the center stand. We'll see if the front or rear sensor provides the signal used for the speedometer.
And what's your first name?