Thanks for your replies. I can give an example. Starting in level 1 going up a hill in a certain gear and at a certain cadence and pressure on the pedals. Going to level 2, everything else being the same, I have to put less pressure on the pedals to maintain the same speed. It is very noticeable. Now, going to level 3 or 4 there is absolutely no noticeable difference. I can go up a steep hill on level 2 with the same ease as in level 3 and 4. There is simply no difference. Regarding the sensitivity setting (1004), it makes no difference if it is set to 50 or 90 or anything with regard to this problem. If this is how it should be then levels 3 and 4 are useless. What is the use of having those levels if it does not provide any noticeable additional assistance to the rider?