Customized version of http://www.thingiverse.com/thing:615256

Created with Customizer! http://www.thingiverse.com/apps/customizer/run?thing_id=615256

Using the following options:

block_type = brick
wing_end_width = 2
curve_type = concave
curve_stud_rows = 5
block_brand = lego
block_length = 4
wing_type = full
slope_stud_rows = 1
vertical_axle_holes = no
stud_type = solid
roadway_length = 0
roadway_y = 0
roadway_x = 0
wing_stud_notches = yes
curve_end_height = 0
block_width = 4
use_reinforcement = no
slope_end_height = 0
technic_holes = no
wing_base_length = 3
block_height_ratio = .33333333333
dual_sided = yes
stud_rescale = 1
roadway_width = 0