Never been there on a bike, but have visited 5 or so times
It´s probably the friendliest area of Europe towards bikers, most B&Bs have a safe, covered dry area to keep the bikes, roads are great, bumpy and twisty, and you have the Nordschleife.
If you´ve never been there before, it´s a bit slippery to go out on the track in the wet, also, I´ld avoid riding on weekends when the place is packed, can become a bit intimidating if you´re not familiar with the track.
I always stay here:
http://www.pension-muehlenhardt.de/, have always been received well, great friends now, and as everyone, very accomodating towards bikers. Their coffee is great, a great start of the day, nothing like opening your eyes to a morning while hearing the sounds of tires in agony and revving engines being brought to you by the mist of the mountain, a motorsports fan´s Meca, I´ll have to go there again in August.
Great pizza in Pinochio´s, in Adenau right on the main street, cheap and very good, really good pizza.
Cheap good meals in the place near the bridge in Adenau, the one with the chairs and tables outside, on the left side of the street if you´re coming from the bridge, on the right side if you´re heading towards the bridge, try the Goulashsoup (spelling?) if you´re cold, will make your stomach feel cozy.
A meal in Sabine´s place, the Pistenklause, in the Hotel am Tiergarten, in Nurburg, enjoy the messages and autographed pictures from motoring legends all over the place, talk about rich in history, not cheap like the others I mentioned though, but worth it for the ambiance.
Cologne is nice for a day walking about, worth the not long ride, great places to drink a beer and eat some typical food by the river, also some extremely nice italian restaurants everywhere in Cologne.
There´s a place near a river that I don´t remember the name of that´s a good ride, will get back to you on this, as with a couple more tips I´ll remember later.