I had an interesting discovery this week. After the whole stem valve / floor pump incident on Wednesday, I got a new floor pump, replaced the rear tube, and rechecked the front tire pressure. I found it to be low by 30. Thought that was odd, because I had successfully added air to the front (I thought) just the day before.
Took my bike out on the same ride as earlier in the week. This is is my standard 10 mile, double hill loop that I like to do mid-week.
EXHIBIT A - THE ROUTE PROFILE
EXHIBIT B - A GOOD RIDE
Here is where it gets interesting. I made a graph of my earlier ride on the same route. I haven't figured out how to get my program to keep the scale the same, but what jumps out at me immediately is that the entire ride is roughly 2 mph slower than the good ride.
EXHIBIT C - A CRUDDY RIDE
Yes, there are differences day to day in weather and how I feel and such, but I wonder if maybe, just maybe, the whole stem valve/floor pump thing was a blessing in disguise. What if the gauge on my old pump was significantly off and I've been riding on under-inflated tires all summer? If I find that my rides improve consistently now, then I'd say that is a definite possibility. Time will tell.