Actually the OP says "...I could not care less.'' This is correct usage. I could care less is the incorrect usage resulting in the above question about how much less.
Iv'e been cycling ever since I was a child. I'm 74 now. I used to take longer rides but now I am content with 20-30 miles at much slower speeds than formerly. I'm content just to be on the bike cruising along. I continue to enjoy climbs. I rarely pedal as fast as I can and speed is not important to me at all. It never really was though I did go faster as a young man.