Hi, our race K runs without a thermostat or fan, it runs at around 70-85 deg during a race and if we are kept waiting before the start the overflow will... well, overflow once it gets to 100 but its no big problem, just water. We end up covering up part of the rad on colder days.
We have 2 engines, one is stock, even has the starter motor, the other has stock cams and valves but head is gas flowed and the
ancillary gears for the alternator and starter are removed. That one is started with a foxley starter. Both have k1100 tbs and use our programable engine managment system, no AFM or stock analog electrics..
Only mechanical failure in 2 seasons racing was worn dogs in the gearbox, and that was a standard box out of a road bike with 40k miles. We have a gear cut device that enables full throttle clutchless gear changes, so it shows how much these boxs and the bike in general can take.
Still finished every race we started, infact we just won the Classic Racer magazine F1 BEARS championship here in the UK on the K100, winning 13 out of the last 15 races.
Good luck.
Ben