I rode this route twice both ways in June 2010. It has 4 sections to it, with a lovely lake/cafe stop in the middle at the top. Travelling North a general uphill wide opened corner section aprox 15 miles to the Lake/Cafe, then generally downhill less wide sharper bends to Baden Baden and then ofcourse back again South with the difference of uphill first then downhill. Fantastic bit of road not to be missed!!
Really like this twisty section in this great biking area (the only downside is that so do many others!)