990 superduke water mystery

Hello: I have a real mystery on my hands I hope someone has some wisdome to share, This problem is far from Obvious, 2007 990 superduke, After riding only not on any bench test will it produce the problem, The bike will draw out a pint of coolant out of the coolant recovery bottle every 75 miles and the system has been bled to book spec more than once at a 45 degree angle, No coolant on the ground, No holes in the radiator, hoses, fittings, clamps, No extirier leaks anywhere, No waterpump problems, No water in the oil or filter system, No coolant smell out the exhaust, steam or moister of any kind, bike runs awsome in every respect, New radiator cap, pressurized both cyl to 100 psi looking for bubbles out the radiator also running it with the cap off produces no assumed headgasket leak, I have not put a pressure tester on the radiator because I dont have one yet however I see nothing coming out the exhaust at all, I have been a KTM Service manager for 20 years And have had years of training on theses bikes, I now longer work for the dealer so no longer have factory support, I could really use some help on this one, Please keep in mind that I am not the smartest guy on the planet but do have alot of years working with ktm, I have only one real thought that carries any weight that somehow someway it is drawing coolant in a small breech in a headgasket under hard decell 'cyl vacumm but as I said there is no signs at all of this in the exhaust, Last I beleive if it had a cracked cyl that once again it should shows a ovious sign in the oil inthe engine or pressurize the cooling system, It has consumed a full container of engine ice in 200 miles with No signs where its going, I have never been face with something so puzzling, Not Obvious, Thank you so much for any help,

How many times has this happened? How many 75 mile rides have you been on where coolant has been drawn out of the overflow bottle?

Reason I asked is my buddy had his valves done at a shop and they removed the radiator to get at the front cylinder. They bled the system once re-installed but he had coolant being drawn into the engine from the overflow bottle for 3 of 4 rides before it stabilized. He thought for sure it was the pump seals (again) but I suggested he continue to ride and top off as I figured it was just drawing coolant in to the motor. I was correct.

John

You could install a catch can at the overflow line to make sure that's not the place you loose the coolant.

Hello: The bike has consumed double the book spec amount of coolant, It shows no sign out it on the engine cases,ground,oil,exhaust,airbox,steam or smell, I did put a catch can on the catch bottle and also ran it on the bench until it was smoking hot and the fan was running and the bike did not displace coolant it seems to only happen when you ride the bike thats why Im grabbing at straws thinking poss under super hi vacuum ' hard decell' its poss drawinging it in though the head gasket but I am not going to put gaskets in until I am 100% poss, Ideas?

Shagged engines are rare on SD's soooooo,

What milage has it got? Climate you ride in? is the fan working?

Im thinking water pump seal OR was not elevated at the front when the coolant was added (appreciate you say its taken double coolant intake).

Not always obvious when water pump seal goes:
viewtopic.php?f=5&t=11519&hilit=water+pump

Correct me if Im wrong but if the waterpump seal was bad it should be leaking in the engine causing the oil level to go up and turn the oil milky, I have checked the oil and filter twice No sign of any water and there is No water on the engine in the engine or on the ground, The fan is cycling normaly, none of this makes sence where the water is going, Its far past any air in the system, 2 full liters have been added to the system after the system was refilled and bleed of all air, At this point a total of 4.4. I am totally stumped, 17000 miles on the bike.

It might be a coolant hose leak that occurs when the system is under a certain amount of pressure in combination with road vibrations (since it wasn't leaking on the dyno). The coolant will evaporate without the pressure or under the heat of the exhaust close by.
You could let the engine get hot and wiggle the hoses a fair bit to see if there's a hidden leak.

Checked all hoses and fittings while smoking hot, Tugged and pulled on everything, I looked over ever inch of the extierier lines, Please keep the sudjestions coming, As I said this is something that has me stumped and I have multi years in a KTM dealership, Also I openly admite that with all the years I have under my belt I still have alot to learn, This cooling system prob is something that poss my be impossable to find witthout a greater failure but please dig deep and help out a fellow Orange bleeder, Thank you for all comments.

Had a coolent leak on my SAAB this spring. Took weeks to find it. Only leaked when car was flooged. It turned out to be a pin hole leak on a preformed coolent hose. It was putting out a constant small pin hole stream,only when hot hot, that looked as steady as a piece of wire.
You might have the same type of leak that shoots the coolent into the air stream at speed away from the bike.

Another thing is the exhaust catalitic converter, if you still have one, is cleaning the coolent smell before you can detect it from thr tail pipe... that sucker really gets hot.

Do you still have the stock exhaust with the catalitic converter?