Yes, it is slightly difficult to change the cam belt. Here is how I did it. Remove the 2 screws from the speed control circuit board (small circuit board behind cam) Loosen the nut that holds the variable resistor of the same circuit board to the metal support. Note the position of the white cam piece and the black cam gear, try not to rotate these. Slide the white cam piece along with the variable resistor slightly back to expose enough of a gab between the white cam piece and the black cam gear. Install new belt, careful not to rotate the cam parts. Slide the circuit board and white cam piece back into position. Install the two screws and test function, if all OK, tighten nut back down. Finished.