I did the Cabot Trail in 2000, so some things may have changed. I rode the trail with an ex-girlfriend (we made much better friends that lovers).
We drove in and spent night 1 at a motor lodge east of Baddeck. I do not remember the name of the lodge, but they let us stage our car their while we were riding. We rode the next day to Cheticamp campground inside Cape Breton Highlands National Park. This is a full service campground, and pretty nice to boot. From there we rode to Macintosh Brook camprgound (still inside Cape Breton Highlands National Park). This site has some buildings, but you had to boil drinking and cooking water. I don't remember if they had showers or not (somehow I think they did not). The next day we rode to Ingonish campground (still inside Cape Breton Highlands National Park). This was full service and pretty nice. From here we road back to the motor lodge and stayed there before driving down to Peggy's Cove (there is also a nice three multi day bike ride from Peggy's Cove to Lunenburg).
The roads are all paved. Yes you go up and down a lot. The mountains are not that high, but the grade is steep as there are no switch backs. And oddly enough, the mountains are all flat at the top. You go past places to buy lunch and groceries for dinner. The scenery is fabulous, the natives friendly, and the cars few and respectful.
There is a nice map at:
http://www.pc.gc.ca/pn-np/ns/cbreton/images/carte-map.pdfYou can also get an overview at:
http://novascotia.com/en/home/planatrip/gettingaround/scenic_travelways/cabot_trail/map.aspxDanno
