To my one-time personal strength coach's (my son) chagrin, I have flipped to riding primarily and strength training a whole lot less. Basically, I am currently on a one day a week, but intense, chinups, pullups, and dips upper body regimen, which is fine for maintaining upper body fitness since I spend most of my available time for exercise on my bike. As a matter of fact the wife just gifted me a really nice dip bar for my birthday last month. This is the same routine I went on due to an injury a little over ten years ago when I lifted 4 days a week and was carrying about 25 more lbs. of muscle. The doctor begrudgingly allowed me to limit workouts to chins, pulls and dips. Gains were substantial enough that each has been a staple ever since.

At 6'5" and 205 you are not too big (certainly tall, but not big by lifting standards). I'd bet that if you did this routine with intensity twice a week you'd maintain an athletic upper body, though cycling lots is invariably gonna lean you up. My son now clowns me for my "skinny cyclist arms." To which I laugh right along with him knowing that, at 51, I'm in great shape.