I have an '04 640 Adventure, brought with 300miles on the clock in Jan this year.
At 650miles it had it's first service at Bracken.
After about 1000miles I noticed that she was using oil and put in 300ml.
I put in another 100ml 1500miles later.

The 2nd service was done by Motorite who was adamant that I was overfilling the bike, but couldn't show me any evidence of that having occurred (oil in air filter or coming out of the engine breather pipe)

The bike now has 7000miles on the clock and is still using oil at a rate of approximately 100ml every 1000miles.

I ride the bike quite hard and do a large amount of long distance riding, cruising at about 75mph.
There has never been any evidence of smoking, even when I overtop it and the sparkplug is a dark grey/mild black colour.

I have had other KTM owners look at the bike and watch it while I am riding and they agree that it is using oil. I have also spoken to swampy and received his opinion on why this is happening.

Before taking corrective action, I am interested in other theories from all of you gurus out there as to what you think the problem could be/similar experiences.

Thanks
Geoff

(ps. took the bike back to Motorite yesterday to prove to him that the bike was using oil and all he could say was "KTM's don't use oil." Mmm, must be a figment of my overactive imagination then)