On a motorcycle one is much more connected to the environment and I think that is one reason people like them. Its fun to come down into a hollow and feel the temperature change. Smells are also easily detected. Sound, on the other hand, is mostly the motorcycle noise (which can be fun too). Reading this comment made me think it would be really interesting to try out an electric motorcycle.
I heartily recommend trying one. I ride a ZeroSR and it's just a different experience, riding sedately along country lanes allows you to appreciate things in a whole new way. It takes some getting used to though, first few times I stopped it was eerie being able to hear nothing but the traffic next to me rather then the bike itself.
An electric motorcycle probably emphasizes the need for a very well-designed helmet. At 60+mph, wind noise from the helmet could still drown out environmental noise.
In low traffic/back roads on my bike, I can tell if there's a car coming up behind me without having to twist around. Doesn't work if there's other cars drowning it out, and I definitely wouldn't recommend relying on that in most cases, but it's neat.
Bicycles and e-bikes are great. Would love to have a high powered e-bikes/very small e-motorcycle that could go on the freeway (ie., be able to cross the bay bridge. Have yet to see such a thing is America.
I've always said that one of the most rewarding sensations on when riding for fun is the access to the variety of smells and sounds and as someone mentioned, a well designed helmet makes a world of difference.
