The Cabot Trail is a given. You might also consider Advocate Harbour, which is south of Amherst starting at the community of Joggins and proceeding down through Apple River. Great ride with very little traffic and as you ride a sport bike lots of curves and elevation changes. This is a particular favorite of ours because it is a nice 400 to 500 km day from where we are in PEI. The section between Advocate and Parrsboro is often referred to as the mini Cabot Trail. If you choose to ride it you must pay attention to the signage. There are three one lane bridges that have appear with little warning and have claimed many motorcyclists that have missed the posted signs.
A great ride, either on you way to or from Cape Breton is Cape George, which is north of Antigonish. The personal preference is to ride it counter clockwise which makes the start point Antigonish. It follows along the coast of the Northumberland Strait and like the aforementioned is full of curves and elevation changes.
Most of the South Shore of Nova Scotia along the old trunk 3 highway and the many loops off of it are very good. The road to Peggy's Cove, from Bayside to Indian Harbour is all curves. I cut my teeth on this when I was a kid. It is over run in the summer though with tour buses and tourist traffic. Pretty much ruins the experience. The best time would be an early Monday morning.
Another favorite is to take the Wood Islands ferry from PEI to Caribou, NS. From New Glasgow you travel south to Sherbrooke. Here you gas up and back track a few kilometers to then head east toward the Country Harbour ferry. You continue east as far as the community of Lundy where you then head north to Guysboro. From Guysboro you go north to the TCH 104 at Monastery. This route has some rough sections but is challenging and relatively free of car traffic.
To put it all in context I am a 60 year old who rides a CBR 1000RR Honda. My riding partners are a 65 year old VFR rider and a 50 year old Kawasaki ZX-10 rider. We just happen to love sport motorcycles and we actual use them as touring machines as well. I scoff at the idea that motorcycles should somehow be age specific. I am always amazed at the people who ask me, when told I ride a motorcycle, ask which Harley I have. We love all things two wheels but when forced to make a choice sportbikes are it. We are a very disciplined group so that we maintain a relatively safe environment for ourselves and we pose no danger to others with whom we share the road.
Look forward to possibly meeting you next year. You are more than welcome to join us. If you want we can send the details to your smart phone