Lane positioning often comes up in this forum. Often in regard to how much lane you should take/or not take to be given the most room by motorists.
According to the report/research mentioned below 3-4ft from the curb is the sweet spot. At least in Florida. Worth a read.
Florida DOT released this report in Sept.
"Operational and Safety Impacts of Restriping Inside Lanes
of Urban Multilane Curbed Roadways to 11 Feet or Less to
Create Wider Outside Curb Lanes for Bicyclist"
"5.1.3 Relationship between Motor Vehicles Lateral Clearance and Bike Position from
Curb
The relationship between a motor vehicle’s distance from other motor vehicles and the lateral
positioning of bicyclists from the curb is depicted in Figure 6. Intuitively, one would expect that
the closer you ride to the curb, the more lateral separation you have. On the contrary, the results
presented in Table 4 and Figure 6 show that riding closer to the curb results in a smaller
separation. Field observations revealed that when bicyclists ride closer to the curb, some motor
vehicles, especially compact cars attempt to fit in the lane without laterally shifting to the
adjacent lane, hence causing lesser distance. On the other hand, the results show that riding too
far from the curb also results in a shorter distance. It seems that there is a spot between 3 and 4 ft
from the curb that results in the greatest lateral separation between motor vehicles and bicyclists.
It should be noted however, that higher standard deviations were observed. This was mainly
caused by the fact that some drivers choose to stay within the outside through lane while others
laterally shift to the inside lane"
http://www.dot.state.fl.us/research-...977-01_rpt.pdf