Just purchased a 2004 Vintage Speedster. The combo gauge oil temperature indicator barely registers when oil is hot. We measured the oil temp at 180F using a dipstick motorcycle probe.
For information, with the wire disconnected at the sensor on the engine, the resistance to ground is around 175 ohms at the 180 degrees of the sensor. When cold the resistance measures over 400 ohms.
To see what signal the gauge wants, we attached a 0-100 ohm pot to the input and to ground (at sensor wire at the engine) of the gauge (sensor wire still disconnected from the sensor). At 20 ohms the needle is at maximum. At a little less than 100 ohms the needle barely moves.
So how do we get these to balance?
Is the sensor putting out the right resistance? If not what is it?
Is the gauge not working correctly?
Is it possible the gauge is a 6 volt gauge?
Something is not right.
Can anyone help?
Thanks