Maxwell12345: Yes you are on the spot, it is the free revving under load that is damn slow on the XT660.

If any of you have ridden a KTM with flatslide, be a 625 / 660 or a XC or EXC you know what I am after. I know the XC and EXC are competiton bikes that cannot be compared but I know what a huge diffrence the change of carb did to my KTM 640 and the ducatis. I think that the free revving of the XT660 is like a CV carb model, sluggish and with lack of "temperament".

My bike is a Xt660X -2004 with DNA stage 2, snorkel removed, KEV mod but standard exhaust (I like it silent..).
I have considerd a Powercommander but I do not think that it will accomplish what I am after.

Or it could be that simple it is just lacking power? I am used to stronger bikes.

But I also feel the same diffrence on cars, some are with more temperament and throttle reponse. Compare a standard Alfa romeo to a Volvo, both can have the same horsepower and tourqe but it is delivered diffrent.
I would say that the XT is a volvo and the KTM is the Alfa Romeo.