I don't even have a D-Tracker yet, but after the lame Motor Show, it's looking to be my next bike. I like the idea of lighter alloy wheels with less flat tires (no need for innertubes) but I'm not into buying $1800 Marchesinis for a $4500 bike. So after researching the schematics at bikebandit.com, it seems the current model D-tracker (KLX250SF) and Ninja 250R share identical axles for both the front and rear. I've read the Ninja has 3.0" front & 3.5" rear rim widths. I'm guessing the D-tracker has 3.?" & 4" rims? Still, both bikes use the same size tires 110/70-17 & 130/70-17 (from pictures I'm guessing the exact same tires). With narrower alloy rims and no innertubes, I'd guess you'd shed some weight over the D-tracker's spoked setup and make flat tires a simple plug fix. An immediate problem is the D-Tracker has bigger brake rotors (300/240mm vs. 290/220mm) and the front rotor is on the opposite side. Flipping the front wheel and getting new rotors of the proper diameter will correct the side/size problem, but the offset of the rotors and sprocket from the wheel's centerline are my big concern. Some questions from owners of both bikes. 1. How heavy are your front and rear wheels with the tires mounted? If you can weigh your wheelsets minus the axles, spacers, and axle nuts; then we can see what weight advantages either setup has. 2. Centerline offsets. I've made this diagram to measure your wheels. If measurements A and B match, then these wheelsets should be interchangeable between bikes give or take an axle spacer. If B is not identical, rotor and sprocket adapter plates may be needed, but they would be cheap to make. That is why I also need measurements C and D. So if you think this is worth pursuing, please whip out the bathroom scale and some accurate calipers/rulers and post your measurements. http://i749.photobucket.com/albums/xx13 ... 3/rims.jpg Here's some photoshop to see what things will look like.