Fixing the crossing light at 7th St S & 4th Ave S is important and should be done immediately! That said, the reason for the high speed between 6th St and M L K on 4th Ave S, is the lack of timing between the lights at 4 Ave and 6th Ave. If you start driving on 4th Ave S when the light changes at 4th St. you will always meet a red light at 6th St. When that changes to green you will get another red light at 8th St unless you drive at over the speed limit. No wonder pedestrians at 7th St see cars driving fast. Solution: change the timing at the 6th St light on 4th Ave so that one can get to 8th St (a major cross town street, while 6th is not). Driving at or under the speed limit. Traffic people, you can do this!!