First, are you certain the throttle is the cause of the problem you're having? (whatever problem that is)
Next, is it a potentiometer throttle or a hall throttle?
A multimeter can be used to tell which you have. Disconect throttle from bike wiring, then set meter on ohms, black to one of the three throttle wires, red to one of the other two. turn the throttle grip or lever from min to max, and if the meter reading changes smoothly from low to high or high to low values, i'ts a potentiometer. If not, move the red wire to the last of the three wires, and try again. If it still doesn't change, then eitehr there's something wrong with the wiring or pot, or it is a hall type throttle.
If you're still not sure, you can open it up and see if there's a tiny black box with three wires, or if there's a big metal cylinder with three wires and a knob/post sticking out of one end. The former is a hall, the latter is a pot.
Both types exist and are easy to find in grip type (and sometimes in thumb type), but you'll have to check which one it is, and note where the wiring connects (because nothing except the original throttle will just plug in and go).
If there are other things on the throttle unit like switches or indicator lights, you may need to leave the original throttle on the bars to keep those, moved over to leave room for the new throttle.