I have a 2003 K1200GT with 27k miles on it. The gauge keeps reading a bit above the normal marking and did some readings.

I wondered if a few of you would repeat my tests for comparisons on a similar GT or RS bike.

Testing details: Bike on center stand idling from cold. Summer temperature here was 90s in the shade. I used a Harbor Frieght $26 Ames model with the factory default Emissivity setting of .95 . Not an expert on emissivity, but that was the factory default. I just pulled the trigger and it read out the digital number.

I pointed the laser at the radiator top black metal curve both left and right sides. On the left side, just off to the side of the radiator cap. Right side, just on the curve. Reading is much different pointing to the hose, so stick to the black curved area.

Instrument was resting on the plastic panels about 3 inches above the radiator.

More definition: “midpoint” I am calling the normal center marking on the gauge. “3/4” is half way between the center marking and Red line. Red line is the Red line area.

Per Clymer manual has “normal operating temps of 190F - 220F. Fans on at 221F and overheated light at 239F.

My results to compare:

Cold, reading was 90F both left and right sides. Gauge, no reading.
After warm up idling - Left 200F, right 190F. Gauge at midpoint.
Guage hits 3/4point - Left 220f, right 218F. Gauge at 3/4point.
Fan on - Fans turn on with left side 224F, right 221F. Gauge 3/4 point.
Fans on 3+ mins - Left 215, Right 205F. Gauge dropping below 3/4 point but not midpoint yet.

Clymer spec and this infrared thermometer is telling me the bike is running in a normal temp range of 190 to 220 although the gauge is saying the bike is running on the hot side at the 3/4point. I wish the 220F on my bike was showing the midpoint on the gauge. For me, not happening.

Let me know how your bike is showing. Much appreciaed.