That kit looks OK. You need the 15C cassette version. If you want to order, show us what options you are planning before ordering. It's 145mm wide, so you will have to stretch you frame a bit to fit it in, and you may have to dish the wheel too to get the rim central in the frame. That's normal with cassette motors.
One important thing. It doesn't tell you the motor speed. All electric motors have a maximum speed, which is fixed, no matterhow much power you five them. A motor makes its maximum power and efficiency at about 75% to 80% of its maximum speed. If you want to ride at 40km/h, you ned a motor has a maximum speed of 50km/h, which is approximately 400 rpm. Most sellers don't have a clue about these things. You should never buy a motor without knowing its max rpm unless you would be happy with 25km/h. You should ask the supplier about the speed to see if you get a sensible answer from them.
One important thing. It doesn't tell you the motor speed. All electric motors have a maximum speed, which is fixed, no matterhow much power you five them. A motor makes its maximum power and efficiency at about 75% to 80% of its maximum speed. If you want to ride at 40km/h, you ned a motor has a maximum speed of 50km/h, which is approximately 400 rpm. Most sellers don't have a clue about these things. You should never buy a motor without knowing its max rpm unless you would be happy with 25km/h. You should ask the supplier about the speed to see if you get a sensible answer from them.
