I found this document, defines what Evenstar is referring to.
http://www.nhtsa.gov/people/injury/e...oc/nhspeed.pdf
Interesting points in this document.
1. Notice the words "Based on engineering and traffic investigations"
2. Minimum speed
3. Local govt can change speed limits "based on engineering and traffic investigations"
Evenstar, I'm with you on this one, we should mimic the state's speed limits ground rules for highways/roads and based the limits on ENGINEERING AND TRAFFIC INVESTIGATIONS not another lake in another state. And people should not be putt-putting around LOL!