does anybody knows where is the strip connection for RPM on DS650 2001?. I've got one but I don't see anyplace to connect it.

 

I'm guessing you are talking about a tachometer? If so, you get the RPM signal from either of the ignition coil wires. The DS has 2 coils, one on each side in front of the gas tank. You may need to remove the front plastic and gas tank to expose them. Attach the RPM signal wire to one of the coil wires - the small wire, not the big one going to the spark plug.