Hi yguerrero2010,
The loop and the time set in the Attribute manager define a specific type of loop; it will be more of an oscillation. The given animation length will always be the starting part of the total duration. In other words, the newly given loop time is pretty much where the initial starting keyframe will be repeated.
The speed of your object is not the problem here, but the added time should be in agreement with it. IF that was an unrelated question, then move the keyframes closer together, speeding up any change. The more vertical a curve is, compared to a more horizontal orientation, the greater the speed will be
Please have a look here for some comparisons.
https://help.maxon.net/c4d/s24/en-us/Default.htm#html/CTBASE-ID_CTRACK_PROPERTIES.html#ID_CTRACK_AFTER
If you share a scene file with a single object that illustrated your animation, I will take a look at it. Please note that Cinema 4D files need to be zipped when you like to attach them here.
All the best
