How are you Jass? You are amazing! You have clarified many doubts for me. I hadnīt considered the pitch before and the quality it brings. As you said, it is true that we think that the bigger the engine the better. It is very interesting your idea of changing the ratio of the pulleys to get more resolution or speed and considering the torque. With all the information you gave me I have decided to restart my project. I will remodel these aspects with the solidwork software and I will most probably ask you some questions if you do not mind. Thanks a lot!!