25 Kg pull? more times not

Is a bit too weak in the chest. Enjoyed my shutters weighed (15.8 Kg) and the motor has miserably abandoned after 1 third of the way.
The given 25 Kg therefore seem a bit high seized me.
Of course, even the frictional resistance happens, you should actually be measured with a spring balance to the belt tension and not only the dead weight per surface formula or scale.
Now I have the 60 engine in it and it runs just fine. In the small price difference I would advise everyone to the more powerful engines.