I have a 2000 and it has started to over heat, as soon as the fans kick on it spits and sputters and dies, have changed the coolant. Thought about unplugging the fans to see if they are the problem, not sure what to do any advice would , thanks
As Robert said you should start by checking the engine-temp-sensor (easier than many other more complex possible cause).
The K1200 has 2 engine temp-sensors:
- one of these will drive only the gauge on dash.
- the other is used by the Fuel-management system (Motronic) and will also trigger the radiator fans at appropriate trigger temp.
Better if you have a GS911, but you can do a rough check of resistance (ignition OFF) using a simple OhmMeter. This PICASSA picture tutorial is for the k1200RS, but the K1200LT has the same sensor - only the end connector is a bit lower (see attached photo...):
At 70F (or 21 Celcius), the reading should be close to 2500 Ohms. When engine is hot, you should read 220 (hot) to 170 Ohms (very hot). Leave ignition OFF for these tests.
Medium Hot will show about half-way on dash (middle white line) and very hot will show a bit past mid-way between this white line and the RED zone. Because we can assume that it is not very proable both sensor will go bad at same time, it is important to compare both the OhmMeter values and the position of needle on gauge. The fans should start when needle is about 1/8 to 1/4 inch below RED zone.
So, do a measurement when stone cold (after 8 hours engine stopped), then run the bike until middle white line on centre-stand, turn ignition OFF, open connector and do another measurement. Repeat this routine when very hot after the fans have started. Do not disconnect this temp sensor while ignition is ON, unless you want to force a Fans trigger (the EFI will run fans full-time when it sees abnormal sensor values - zero or infinite resistance).