Mine last night at 6036 miles
Yesterday was probably the warmest day of the year so far here in the UK ( a massive 21 degrees C / 70 F ) have spent alot of time riding in much colder temps, maybe I should have stuck to riding in winter. About 25 miles into my ride I noticed there was some vapour / smoke coming off the bike but I wrongly assumed it was a bit of cleaner still burning off the exhaust (as I had wiped it over before setting off and yeah that doesn't look too logical now, it probably all burned off in the first two miles).
Not long after, I'm heading down a long downhill stretch and on a fully closed throttle for part of it I drop to under 60mph (due to the designated speed trap location at the bottom of the hill) and with plenty of time to take in what was happening there really was no sign that anything was amiss (the motor would have been cooling off a little at this point of course).
Speed trap site well and truly passed and I start to wind it on again, still nothing that obvious but at the bottom of another big hill I think I first noticed the fan running, didn't think too much about it as I've had the fan run on cold days when in town. Gas it away from the junction then stopped at some lights a couple of miles later I notice some more smoke, look down and see coolant all down the side of the bike and a high coolant temp warning on the dash. Temperature gauge only went as far as the H point (there are still 2 or 3 bars above it) so I'm guessing the motor will be fine.
Once it had cooled a little I restarted it (yes I know not advisable) it blew white smoke out of the exhaust for maybe 3 seconds then it cleared and looked and sounded fine, so I'm thinking it's only a partial breach that happens when the motor is hot (although suppose it could be that there was not enoigh coolant left in the system for the motor to still ingest.
The header tank level has risen from min to max and I think the coolant down the side of the bike has come out of the radiator cap - all pointing to the engine pressurising the system.
Bike is 2 months out of the KTM warranty but still 30 miles
inside when the second service was due (because first service was done at 1407 miles.......)
Have just come off the phone to my dealer - I admitted the bike is not 100% stock, as would have been too much effort trying to put it back, not least due to the 60 odd holes I drilled into the back of my 2015 fan shroud.
Dealer reckoned that if KTM know there was a problem with that production batch they will just sort it and 2015 models appear to be particularly prone I think.
If they wont cover it, well I've already had the cams out to do the valve clearances, would not have thought it would be much more work to get the head off.........