So much good advice in this thread, it turned out better than I expected. Thanks, everyone.

Just to clarify, the "tiredness" I referred to in the morning is not due to eyes open at 5am or the two mile walk...just groggy from probably not going to bed at a time that corresponds with the alarm clock going off the next morning.

It is more emotional fatigue in the afternoon. All the cars coming at me (not much traffic with me)...I can't maintain the level of focus I feel is necessary to be a safe rider.

Steve pointed out something that I am betting is true...my analytical nature is interfering with the pure enjoyment of motorcycling. Being an analytical pays dividends at work, but often is a hinderance when it comes to anything emotional.

I took an 85 mile ride tonight. I actually felt myself leaning back and enjoying the breeze for the first time in a long time this evening. What led to that? No rush, no heavy traffic coming at me or with me, great scenery, lots of cruising, less stopping and shifting.

What a relief it was to feel good on a bike again.

I will probably continue to commute on the bike - on a part time basis - perhaps once or twice per week when I am in one building for the day, feel good in the morning, and can sneak out a few minutes early to enjoy a different route home.