Today I’ve been very stupid with my Triumph…
On way home from holiday on Friday I had engine temperature warning light come on whilst stuck in traffic, so I resorted to killing engine at stops until on open road where things seemed fine. Sure enough, when home found fan wasn’t coming on, so today I set about investigating.
Following trusty Haynes manual I first checked the fuse, which was fine, then got at connector under tank, but not having handy cables I thought that instead of putting 12V from battery onto fan wire to test it, I’d be easier to get TuneECU to do fan test and look at voltage with multimeter. Sure enough, I could hear relay click and 12V appear on connector so decided problem was with fan, bugger, a new one costs £250.
Even more of a problem was actually getting at fan, I could unbolt it easily (thankfully no rusted fasteners) but to get it out I would have to take radiator off. So I drained the coolant system and tried wrestling it out. Not meeting success I resorted to subscribing to Triumph service manual to see what the ‘correct’ procedure was. Found out that was to remove the engine cradle, the same cradle which I had jack under supporting bike. 
In the end I resorted to sacrificing blood from my knuckles whilst using three small screwdrivers like mini tyre irons to get coolant hose off engine. Only then with radiator and fan off I decided to double check it by connecting up to battery, and the fan worked! And to add to my stupidity, I had fan resting on seat and the blades put a slash in the coccyx cushion. (I have a spare for an old seat fortunately).
So, it seems like fan problem is a high resistance in the wiring or relay which are probably very inaccessible, so it’s time for a stiff drink and return to this tomorrow…
Forks are out, because I’d decided to referb them and do headstock bearings. Also on the list to do is chain and sprockets as the 1000 mile holiday had produced 20mm extra slack so chain must buggered (done 25k miles so not too bad).