Getting A Baseline

I've got a short out and back route near my house that I have used as a very rough gauge of early season fitness for about 6 years now. At just under 21 miles and perhaps 400 feet of elevation gain, with low traffic and perhaps 3 stop signs, it's a great little "time trial" course.

My best time on this route was exactly 5 years ago today, at 56:45 (22.0 mph) [gps link]:

 Today I rode it in 1:00:01 (20.8 mph) [gps link]:

20.8 is faster than I expected, but slower than I hoped. I was really trying for 21. Looking at the speed profiles in more detail, it's clear that I'm consistently 1-2 mph slower than in the past.

A couple factors that I've noted:

• I'm about 20 pounds heavier now than I was in 2008. Even with only ~400 vertical feet on the route, I think this makes a big difference. Even on this flat route there are rollers where I slow down to 14mph, over which I used to sprint with only a minor slowdown.
• I'm not able to maintain a sprint for nearly as long. In the past I could stand and sprint over a small hill for 1-2 minutes before really feeling gassed. Now that's more like 20 seconds, and recovery is taking longer as well.

Clearly step 1 is to lose some weight. Step 2, I think, is to keep climbing hills. There's another route near this one with a 1000 foot climb, that makes a good 'big ring' climb. Step 3 is to build up my fixed gear which, in the past, seemed to contribute substantially to increasing my top speed. Presumably because when geared appropriately (my old Steamroller was at 80 gear-inches), you don't really have any choice but to ride fast.

I plan to ride this route as a TT every couple weeks. I've always felt like 23.0 mph on this route would represent a fitness level that I'd feel pretty good about. I doubt I can hit that this summer, but getting back to 22.0 would be a start.