Note: all microsoft model for internal customer only, not for public use !!!
Step 1.
search zip code or address, where you want
Step 2.
click the street you want, speed limit will show up
Step 3.
model 31728 is here
https://transparentgov.net/json2tree/esri/server/folder2.html?org=https%3A%2F%2Fpublic.gis.lacounty.gov%2Fpublic%2Frest%2Fservices&url=https%3A%2F%2Fpublic.gis.lacounty.gov%2Fpublic%2Frest%2Fservices&arcgis_online_token=&timeout=9000&select_folder=28&select_layer=0&select_folder_text=LACounty_StreetMap+%3Csup%3EMapServer%3C%2Fsup%3E&select_layer_text=0+%26%23x21E2%3B+Cities+and+Communities+%3Csup%3EFeature+Layer%3Csub%3E+esriGeometryPolygon%3C%2Fsub%3E%3C%2Fsup%3E