Karlp,
My story is much the same regarding the XR to KDX. I have the same bikes and my XR4 has been sitting since getting the KDX 220. I too thought my XR was the best bike on earth. Now it feels heavy,tiring to ride (due to the weight), turns poorly, brakes poorly, and is poorly suspended compared with the KDX. The XR has race tech suspension and I like the stock KDX suspension better, soft front spring and all! I used to think poorly of 2-strokes but now I realize that a KDX is really no worse to maintain then an XR.Everything except the engine is really the same to maintain and rebuilding the engine on the KDX was easy and cheap, compared to a 4-stroke. I would rather rebuild my KDX once a year for $130 then ever face the massive bill of an XR rebild. The KDX is a lot nicer pushing on to the truck as well. I suppose we are converts!